why you're not losing weight on phentermine

Why You’re Not Losing Weight With Phentermine

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Phentermine is undoubtedly an extremely effective weight loss medication, but for all of those who experience weight loss success, there are some who are left wondering why they’re not losing weight with phentermine. While it could be that phentermine has stopped working for you, if you can still feel the effects of appetite suppression and added energy, then it could be for one of these reasons.

1. Eating Too Much

Counting calories can be a pain, but it’s a good way to allot how much food you can have at each meal and for each snack. In addition, it’s also important to weigh your portions as you could be overestimating how much you’re meant to eat of certain foods; test how accurate your judgment is by portioning your food as you normally would and then weigh it out afterwards. If you’re consistently serving yourself generous portions then you could be consuming A LOT more than you think, therefore making losing weight with phentermine more difficult.

2. Not Eating Enough

Phentermine works by suppressing appetite, but sometimes this effect can be too strong, to the extent that people have zero appetite and can struggle to eat anything all day. You may think that less food = more weight loss, but as we explain here, that’s really not the case; there is an ideal amount of calories that you should be eating to successfully lose weight, and getting that balance right is the key to losing weight with phentermine. If you’re consuming too few calories each day, your body’s reaction is to think that there are lean times ahead, meaning that it will turn your metabolism right down and cling onto any fat that comes its way, i.e. you are less likely to lose weight.

3. Not Getting Enough Sleep

Establishing a healthy diet and becoming more active will help you to shed pounds, but lifestyle factors such as getting enough sleep also play an important part in your ability to lose weight with phentermine. When we lack sleep, our brains crave unhealthy easy foods, and our hormones tell us that we’re hungry when we’re not. This is clearly not a recipe for losing weight with phentermine, so make sure to make sleep a priority and get at least 7 hours every night.

4. An Undiagnosed Health Issue

Before prescribing phentermine, your doctor should check that you aren’t suffering from one of the many health issues that can cause weight gain or make it difficult to lose weight. These health issues can include a vitamin or mineral deficiency, such as anemia, Polycystic Ovary Syndrome (PCOS), diabetes, or an under-active thyroid, among others. If you haven’t been fully checked for these types of issues and losing weight with phentermine is proving to be difficult then ask your doctor for a full health check-up, even if just to eliminate these as potential reasons.

5. Not Getting Your Vitamins

Deficiencies in vitamins and minerals lead to a sluggish metabolism and slow bodily processes, meaning your body has to work extra hard to process the food you eat, and as a result, losing weight with phentermine is more difficult. So, make sure you get the recommended daily requirements of important weight loss nutrients to get better results. That said, it can be difficult to eat enough of a variety of foods to meet all these requirements, so we recommend Phen Vites, which contain all of these crucial vitamins plus added premium ingredients like 5-HTP to help boost your weight loss potential even more.

why you're not losing weight with phentermine

6. Too Stressed

Stress can be one of the underlying reasons for weight gain, so it makes sense that it’s something that needs to be addressed in order to lose weight. One study found that participants taught stress-management techniques were able to lose significantly more weight than the participants who weren’t taught these techniques, even though their diets and activity levels were the same.  Reducing stress balances out hormones and allows your body to function better, so you should aim to reduce your stress levels for success in losing weight with phentermine. Click here for some great ideas on how to manage stress.

7. Not Exercising

Many people rely solely on diet to lose weight, which can be effective to a certain extent, but it’s the combination of diet and exercise that really gets results. Unless you’re unable to exercise due to injury you should get moving every day, even if it’s just walking for half an hour. If you find it hard to get motivated to exercise, check out these ways to make exercise more fun. Exercise is a great stress reliever, adds to your phentermine energy boost, and, research into long term weight loss has consistently found that exercise is the key to losing weight with phentermine for good.

8. Eating Too Many Empty Calories

Losing weight with phentermine isn’t all about eating less, it’s more about eating better. And the same is true of your calorie allowance; just because two foods have the same amount of calories does not make them equally good for you. Furthermore, low calorie or low fat options aren’t always the way to go, so try to avoid light, low fat or specific diet foods as they often substitute healthy fats or calories for added sugar or salt and can be more processed than the regular foods they aim to replace. Instead, aim to get goodness from your diet by seeking out foods packed with vitamins, minerals and healthy fats, avoid anything overly processed, and fill up on fiber and protein to keep hunger at bay for longer. You should also watch the calories and sugar you consume in your drinks, as liquid calories can really add up without giving us any value for money as far as goodness goes.

9. Not Drinking Enough Water

Drinking water has so many benefits for those losing weight with phentermine; water suppresses your appetite by filling you up without the calories, it helps your body work better and boosts metabolism, maximizes the effects of phentermine, relieves side effects, and it helps you drop water weight. Make water the ONLY thing you drink and you’ll be sure to see a reduction in side effects, a healthier you and improved weight loss results. And, for an extra weight loss boost add the ultimate detox, Phen Drink to water to see even more success.

10. Not Challenging Yourself

If you’re starting from zero then phentermine will give you a huge burst at first, but too many people continue on automatic pilot and expect to see these great results all throughout their phentermine prescription. Instead you should see it as a learning process, where you expect to progress and improve in all aspects of your life, and not just as a means to an end. So, challenge yourself continuously to eat better and be more active by setting new targets and mini-goals to keep your interest up and you’ll be sure to enjoy more success losing weight with phentermine.


Could one of these reasons be why you’re not losing weight with phentermine? Let us know by commenting below!


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67 Responses

  1. I just started using phentermine and I don’t have mood problem. I’m still have and appetite I exercise before I go to work.I eat breakfast lunch and dinner. One thingi notice is im very tired. I mean my metabolism is very low.my questions is can I take and energy drink to boost it.

    • Hi Jay,
      If you’re tired it could be a side effect of the phentermine. We would advise you to try more natural methods to increase energy first, such as drinking water, sleeping at least 7 hours each night, and continuing with the exercise as this will help to increase energy levels. We would not recommend that you drink energy drinks as these are made up of chemicals and sugar, both of which will make phentermine less effective and will not help your weight loss efforts either. If your lack of energy continues then you could try the weight loss supplement Phen Caps which we recommend for added energy and appetite suppression to boost your phentermine. Here is a link to find out more: https://www.phen.com/
      Hope that helps!
      Sally, phentermine.com

  2. I’m taking Phentermine 37.5 mg. For almost 2 months now I started last month & I have not felt anything no weight loss, I have had the gastric by pass surgery done, I really can’t do any exercises, my knees prevent me I have severe arthritis in my left knee but it’s in both knees, I do diet I always buy fish tikapua, frozen veggies, fruits usually bananas, grapes, cantaloupes, honeydew melons, so my question is why am I not losing but gaining it all back, I was on belviq for a month my INS wouldn’t cover it; it’s too expensive for me, so help me out here what am I doing wrong, little today bit I do lack sleep I’m Lucky to get at least 3-4 hrs of sleep; I chew ice cubs cause I retain fluids

    • Hi Donna,
      The lack of sleep could be a factor, and retaining fluids would mean that you’re less likely to see a drop on the scale even when you have actually lost fat. You could try upper body exercises which would help to build muscle, and swimming is usually a safe exercise even for people with injuries. Do you feel the effects of phentermine, such as a suppressed appetite and more energy? If not then it may not be working for you like it should.
      Sally, phentermine.com

      • I take 200 mg daily and I am hungry and tired

  3. Which are better? The pills or the caps

  4. Menstrual bleeding ever since I started taking phentermine x16 days ago?

    • Hi Shelley,
      This is not a typical side effect of phentermine – you should talk to your doctor straight away.
      Sally, phentermine.com

    • When I started taking them it stopped my period. I researched it and several people had the same thing happen to them.

    • Happens to me every single time I restart my pills and lasts for weeks

  5. I’ve been on adipex/phentermine for 2 weeks.. I know not a long time. I have lost 4 pounds.. the problem is, is I keep gaining weight back. I started at 240, I went down to 233, then I’ll gain back 2-3. I eat 1000-1200 calories a day. And I exercise. Could the problem be my thyroid? I am on synthroid and getting half my thyroid removed. Once I get it removed will my weight loss from phentermine get better? I need this to work, I feel like I’m out of options.

    • Hi, I am having the exact same issue. Is it pointless to take phentermine until your thyroid levels have balanced? I really hope they answer this question.

      • Hi Shannon,
        This would depend on the individual and what their doctor thinks is best for them. For some people is is more helpful to get their thyroid levels balanced before they start their weight loss journey with phentermine, but for others the whole process works better with help from phentermine to suppress appetite and boost energy while their levels are normalizing. Talk to your doctor about what he or she thinks is best for you.
        Sally, phentermine.com

  6. Hi, I started taking phentermine and am on my 2nd week. I lost 7 pounds but on Monday when I started my 3rd week I gaind 5 pound it just doesn’t makes sense – I exercise 5 days a week and drink 80 ounces of water a day. For breakfast I eat 2 eggs with spinach, for lunch I have a chicken salad, and I hardly ever eat dinner maybe a cereal once in awhile. Can someone tell me what I’m doing wrong I’m so disappointed

    • That was posted last month, have you lost any yet? I’m in the same boat. I exercise 5 times a week and I eat 1200-1300 calories a day. No weight loss in 2weeks

  7. Only lose 5 lbs a month
    I still feel sluggish during the day and can sleep but can’t sleep at night I’ve been on adipex 2 months – cravings don’t deminish as I am a extreme binge eater of 16 yrs not by choice but by habit. I try to eat three small meals but find myself getting sick so I got stuck 160 weight after kids and can’t get back down 🙁 why isn’t it working for me like it does my friend who is a nurse?

    • And I am very active I push 5miles every other day drink only water and eat veggies raw yum I love my veggies just thought I add

  8. I started Phentermine on 4-28-2016. So far I’ve lost 18 LBS! I drink half my body weight of water, eat healthy and exercise daily. I burn almost 800 calories every day. I do a lot of the incline on the treadmill and elliptical, even cardio! But I still fit in my same pants size. I started off at 260, to 242. I have two more months left with phentermine..

    • I also started the same same day 4/28/16 on the first month i lost 16lbs im already on my 3rd month feeling great havent weighed my self though till i go back on August 11th…… 🙂

  9. I started this 8/6/16 weighing in at 223 at the doctors office but then I weighed myself with my own scale on 8/9/16 and weighed 211 so I really don’t know which scale number is correct because it is impossible to lose that much weight in like 2-3 days and I don’t feel the difference, but it’s probably the 223 lbs that I probably weigh, so I probably still weigh the same. Anyways, ever since starting this I’m even hungrier than before starting this pill, I eat a normal meal and then start to get full, but after like a half hour I get really hungry and nauseous, and my stomach feels empty. Today I kind of felt a little dizzy that I thought I was going to pass out, but I didn’t since I rushed to the kitchen to eat something. I also feel weak and sluggish but not tired, and it is really hard to go to sleep at night and go back to sleep because I take this pill at 6 am and then go back to sleep since I normally wake up at 11 am or around noon, but I’ve basically been sleeping for like 3-4 hours ever since. I don\’t know but ever since starting this I feel like sh!!!t but very wide awake which I didn’t before because I always felt tired before taking this pill. Maybe I need to lose weight the normal weigh… (haha get it? lol ill stop.)

    • Sorry I meant to say I weighed myself on Sunday August 7th, not today.

      • Sorry forgot to add more…

        I have a gym membership that I haven’t used in months and I would love to go back or at least go to the nearest trail and walk but I’m afraid that I’m gonna pass out since I feel weak-ish and feel heavier and sometimes I feel like my eyes want to go dizzy but I don’t end up stumbling or anything.
        I don’t know, I probably need to stop taking this.

  10. Lost 5lbs first week, one lbs the second week. I’m on my third week but my husband threw my pills away so I’m not on them this week and I feel bloated!! 🙁 my Dr won’t Rx them until next week bc they only allow 7 pills a week. I weighed on my home scale and it looks like I’ve gained back almost all the weight I’ve lost!! 🙁 how and why I don’t know, I sleep enough, I walk a mile every day twice a day, I eat one cup of food per meal as directed by my Dr and only what’s on the plan and have my three snacks which of course is veggies or a fruit, also only approved items on the list and even got my shots to boost energy. I take b12 and b complex and iron for my anemia. What could be wrong that I’m gaining ??? 🙁

    • Hi!
      The weight gain might be related to the bloating you’re experiencing. It could be related to your menstrual cycle, not drinking enough water, a food intolerance, or if you’re suffering from constipation as a side effect of phentermine. It’s not possible to gain that much weight in a week so it’s more likely to be water weight. If both you and your doctor think that this plan is the best way for you to lose weight then it shouldn’t matter if you are taking phentermine or not – phentermine does not directly cause weight loss, it just helps you to stick to your plan, which you seem to be able to do without phentermine. Just keep doing what you’re doing and stay strong! 😀
      Sally, phentermine.com

  11. I am currently taking phentermine. I still feel the energy but I do feel hungry during the day. Does that mean its stopped working for me?? Also, I weighed myself this morning and weighed in at 164. I got back on the scale when I got home from work and I weighed 165. Why?! I’m taking birth control so maybe that’s interacting with it and causing my weight loss to slow down??

    • Hi Jessica,
      This is the problem with weighing yourself too often. Your weight increases throughout the day due to the food you’ve consumed, liquid levels in the body, salt etc. You also get shorter throughout the day but then at night your body is still running, using the fuel consumed throughout the day while also stretching out your limbs and muscles, so that you wake up taller and lighter than you were when you went to bed. You should only weigh yourself in the morning before any food or liquid and ideally just once a week as that’s when you notice the overall difference, rather than becoming preoccupied with these ups and downs of a pound or two here and there which happen constantly throughout the day. Contraceptive pills haven’t been found to interact with phentermine so these are unlikely to affect your weight loss. And, with respect to still feeling hungry, only you know if this hunger is more or less than you used to experience. But, it is normal and correct to still feel hungry on phentermine – it isn’t designed to completely remove hunger. These tips on how to suppress appetite should give you some advice about the types of foods which will keep hunger at bay for longer: https://www.phentermine.com/blog/10-tips-suppress-appetite-phentermine/
      Sally, phentermine.com

  12. I am not sure if anyone still uses this blog but I have been on phen since Aug 9th. I have lost 15lbs but over the last week I haven’t lost anything at all. I eat oatmeal for breakfast, yogurt and a fiber one bar for lunch, and usually chicken breast and a veggie for dinner. I am also working out 5 days a week. I cant seem to lose anymore although I am nowhere close to a normal BMI. Is anyone else having this issue?

    • Hi Shaunte,
      The blog is where we post articles about phentermine and the comments on them are usually questions for us to answer. You might find it better to post in the forum to share your experiences with other phentermine users and to ask for advice. Here is the link to sign up if you’re not a member: https://www.phentermine.com/forum/register.php.
      In answer to your questions though, I have a couple of suggestions. Firstly, losing 15lbs in less then 3 weeks is really great and something to be celebrated. However, weight loss is not always linear – it is not typical to lose consistently every week, so this stall isn’t permanent, your body just has to adjust itself to take your losses into account. Secondly, it doesn’t sound like you are eating very much. I don’t know if you’ve just outlined a few of the things you eat, but you should be eating at least 1200 calories a day – oatmeal is great for breakfast but adding some fruit would be better, lunch should be around 300 calories and should incorporate some vegetables or legumes for fiber, protein and nutrients, and then your dinner seems fine. The fiber bar and yogurt would work better as snacks, and maybe add some sources of healthy fats to your diet such as oily fish, avocado, nuts or olive oil, as well as more whole grains, such as brown rice, quinoa or whole grain pasta. Hope that helps!
      Sally, phentermine.com

      • Thanks Sally. As far as my diet thats all i have been eating every day since i don’t have much of an appetite.

  13. Hi , I was on phentermine 2 years ago for 3 months and lost 30lbs. It suppressed my appetite and worked great. I just started it again one month ago and feel no different taking it (like I did before) & have not lost any weight. Does it just stop working as effectively as it did the first time you introduce it to your body? Nothing with me has changed over the past two years, so it leads me to believe it’s no longer effective.

    • same here 🙁

      • I lost 47 pounds in three months a year ago on phentermine. Gained it all back and then some because I have multiple herniations in my back that stopped mobility for a long time. I and in the first week of my second month now. The first month back on phentermine I only lost four pounds. I was so disappointed. But now this month I\’ve lost 8 pounds in five days. Y\’all hand in there. I boostedmy water intake and stayed sweating finally(I\’m not a sweater normally)

  14. I have been on phentermine for 4 months. The first 3 months I lost a total of 30 pounds! Yay! This last month and a half I have completely stalled and am at 180 pounds. My doctor and I have discussed my goal weight and we came to the conclusion that 160 is a good weight. I am only 15 pounds away from my goal and don’t know what else to do. I track my daily food and caloric intake and I eat between 1200 and 1350 calories. I have cut out all sugary and caffeinated drinks and only drink water throughout the day. I walk 30 minutes every other day and more on the weekend. I just don’t know what else I can do to jump start my weight loss again.

    • Hi Rachelle,
      As well as walking it could be beneficial to do weight lifting and also more strenuous cardio such as fast cycling, running, dancing or swimming. Walking is great but it’s counted as NEAT (non-exercise activity thermogenesis) rather than exercise, especially if you’re walking at under 5mph. Plus, as well as counting calories and avoiding sugar, are you making sure you eat plenty of nutritious food, protein, fiber etc? And don’t forget making sure to get enough sleep and reducing stress – weight loss is more than just about diet and exercise.
      Sally, phentermine.com

  15. Yes I believe it is less effective once you take it again after the first time

  16. I’m having a hard time getting my doctor to prescribe Phentermine 37.5 to me here in Florida and I do weigh 154 pds and only 5’2…which typically is very overweight and very common to be able to get it for at least 3 mths. When I lived in Kansas my doctor had no problem prescribing it to me once he checked my blood pressure every month and I still had a little bit to lose. Any recommendations of doctors in Orlando that will prescribe it?

    • I suggest going through a medical weight loss clinic. I was at 181 at 4″11 and my doctor never suggested it, just said eat healthier and take these anti-depressants so you don’t feel anxious -_-. When I got to 205 I decided enough was enough. I went through a medical weight loss clinic and got the RX. My first round alone I went from 205 to 181.

      • What was your typical meals during the 1st round?

  17. Hi,
    I started taking phentermine 30 mg on Dec 14th.
    I am eating well, drinking lots of water, taking Multivitamins and probiotics and exercising 3 times a week but have not lost any weight till now. Should I ask my doctor to increase my dosage to 37.5 mg? If anyone faced same issues, please advise what should I do.

    • I myself am going through the exact same thing I’m on 30 mg I wonder myself if I need a higher dose. I’m working out watching my calorie intake but no effect I started January 24, 2017 and I drink plenty when do you notice results?

  18. I started phentermine in October and in the first month I lost about 15 pounds. I had to stop taking the pills because I was very restless at night time, and to anxious during the night. Since I want to loose 20 more pounds I started them again in January 2017, have not lost a pound, but still can’t sleep at night, feel restless, and constipated. Don’t get very hungry either. Don’t know what to do. Has anyone experience any of this? And suggestions? Thanks

    • Hello Kariannis, thank you for reaching out. We’re not sure if it’s that phentermine doesn’t have the same effect after you’ve taken it before or if the manufacturers have made changes to it, or maybe both. Some people find it helpful to take additional supplements such as 5-HTP or B12, as both have been found to boost energy and motivation on phentermine. Or you could supplement your phentermine with an alternative like Phen Caps to give yourself an extra boost. If that doesn’t work then perhaps your doctor could suggest something, such as a new brand or seeing if switching from tablets to capsules could help. You can find out more about it here: https://www.phen.com

      You are welcome to join our brand new support group so you can connect with other phentermine users, share your experience and get some valuable advice. https://www.facebook.com/groups/1069871763087734/

      Have a nice day!

      Rebeca, Phentermine.com

  19. Hi my name is Liliana I started phentarmine on January 1-2017 the first month I lost 15 lbs. I am on my second month and haven’t lost a lb. I’m down to 180 been there for almost a month, I work out 5x a week and supplement 2 meals for protein shakes. I don’t know what else to do I feel disappointment since I feel I am doing the diet correctly.

    • Hi Liliana,
      As the article above explains, there are lots of factors to consider when it comes to weight loss – you may not be eating enough if you are substituting meals for protein shakes, or possibly getting more sleep or focusing on other lifestyle changes could help get your losses moving again. We would advise you to look at your diet and how you can improve it in terms of nutrition, and also to switch up your work out routine to combine weights and cardio if you’re not already doing that.
      Sally, phentermine.com

  20. I’m in the same boat as Lilana. I lost 11 pounds the first month and now two weeks into my second month only one pound. I’m eating about 1000 calories a day, fruit and lots of water included, not too much fat. I’m sleeping fine every night. I really don’t know what else to do. Also exercising at least five times a week. Any advice for me?

  21. Two summers ago I took phentramine and Prozac combo for about 3 months. I lost little weight. 3 months ago I started again, I lost 6lbs 1st month. 2nd month lost only 2lbs. So my Dr started me on metformin also, minus Prozac. I haven’t lost a thing this month. I workout 45 to 60 mins 4 or 5xs a week. Cardio and strength. I do eat only around 1200 calories a day. Granted not always healthy but for most part it’s healthy. No soda either. I weigh 145 and would like lose 20 more. Any ideas?

  22. I started 37.5mg 2 weeks ago today. I have lost a total of one pound. I have never felt the burst of energy everyone explains. My appetite seems exactly the same but my will power is not letting me eat what I want. Cut out all coffee, tea and sodas for the past 2 weeks. All this and still nothing. Sleep more than enough so that cant be it. Would love some energy. I\’m starting to wonder if the pharmacy gave me a placebo. I\’m so frustrated. I am on synthroid but my Dr insisted this was OK because all my labs have been normal. Please help!

  23. Hi, I have been on phen 37.5 and have been struggling in month 2. My first month I lost 11 pounds. 7 of water in my first week. I am doing HIIT training and intermittent jogging 10 days on 1 day off since I started March 22nd. I cut out white starch flour potatoes bread etc. I drink 100 oz of water daily and I track with My fitness pal and Fitbit. I burn about 2200 cals a day and stay in 1200-1300 cals a day. My diet is fruit yogurt smoothie with nature bounty protein shake. Tuna with 1tbsp of mayo and relish for lunch. Dinner is lean meat and sweet potatoes with veggies brocilli and or carrots. I have never felt my appetite surpress or extra added energy. I have been earning calories back with exercise and I don\’t eat them back. I have a cheat every 2 weeks and total cals are 1500 on those days usually a savory desert. I don\’t have any thyroid or pcos issues. I\’m 41 yo and 5\’1. I sleep great. Even nap sometimes. 6 years ago I was put on topimax and Wellbutrin for season depression. I lost loads of weight. I heard that if patients have used Phen befor it\’s difficult the next time around to see progress. Does it work the same way if I had used topimax? Should I ask my doctor to add topimax to Phen? Is it possible that Phen just doesn\’t work in some patients at all? I feel 11 pounds is a great loss. I also feel I\’ve done a lot of the work for the loss myself. It\’s now been 7 weeks and Ive been stuck between 178-175 back and forth. It just doesn\’t budge. Im not a stressful person but I am becoming stressed with the issues I\’m having. Can someone guide me toward a solution and or suggestion. My doctor told me 2 weeks ago to continue what I am doing. I revisit him end of may. I leaning toward stopping them all together. It\’s overwhelming enough being overweight, to see others lose 15- 20 pounds the first month without exercise baffles me as I work my tail off!

    • Hi Brooksie,
      Speaking with your doctor about your concerns is always wise, so I would definitely encourage you to do that. However, could it also be that you are actually consuming too few calories relative to the amount of activity you’re doing? Check out this article for more info on the importance of balancing calories and activity: https://www.phentermine.com/blog/how-many-calories-to-lose-weight-with-phentermine/
      Rachel, phentermine.com

  24. Started about 2 weeks ago. Lost 5.5 lbs first week and only 1.2 the second week. My doctor said I would lose about 2 lbs a week so im feeling a little discouraged. Could i not be losing weight if i feel like i am eating too much protein over 80 grams on some days? I work out 5 hours a week and only eat 1000 calories a day. I drink over my recommended 64 oz of water.

    • Hi Rosalinda – it sounds like you’re doing great! Remember 2 lbs per week is an average, so with 5.5lbs + 1.2lbs in two weeks, your average weight loss per week is still over 3.3 lbs per week. Above average 🙂
      Rachel, phentermine.com

  25. Hi everyone. I have been on adipex for 1 week now. I work out 4 times a week. I work a very hard working job. I am a CNA and I\’m drenched in sweat most of my shift. I\’m constantly running around, lifting people and working my butt off. For example, today I walked 9miles at work. I\’m 21, I weigh 169 starting (with clothes) and I am now 164.4 (with no clothes) I\’ve lost about 4 pounds which isn\’t horrible but yesterday I weighed myself and I was 163 even (no clothes) I never was a bad eater or \”unhealthy\”. I just have a curvy body and I carry a lot of weight in my legs and butt so I asked my doctor what I could do to help get these pounds off. I eat about 900-1,000 calories a day by choice. My appetite isn\’t gone and I also don\’t have any increase in energy. I can take a nap during the day but I don\’t. I sleep 7-8 hours a night too. I stopped drinking pop (I wasn\’t a big pop drinker in the first place. Maybe 5 cans an entire week MAX) I stopped drinking juice too. I strictly only drink water. I intake about 7-13 bottles of water. My question is how did I gain 1.4 pounds in less than 24 hours.. I did weigh myself right after work (walking 9miles today at work) and I am on my period (but I was on my period yesterday when I weighed 163). I also take Wellbutrin XL. Can I be more bloated today and that\’s why I\’m 1.4 pounds heavier? I\’m getting really depressed with not seeing the number going down but it\’s going up. Sorry for my language, but I am working my ass off. I take vitamins every day too. I\’m doing everything \”right\” do you think the 1.4 gain is from being more bloated today? Please help me with advice. I\’m feeling like I\’m failing when all I\’m doing is trying non stop to drop this extra weight off. My wedding is coming up and all I want to do is drop 30 pounds and feel so confident at my wedding. Thank you.

  26. If you had energy when you first started taking phen then it went away, its more than likely a combination of two things, 1) body adjusting to phen 2) lack of quality sleep. Once I started taking a sleeping aid at night, I noticed that my energy started to return. It was nothing like the first two days but I was no longer feeling like a slow-walking, energyless zombie that could not sleep.

  27. Hi I have a thyroid issue it is hyper active I had radiation iodine done but to no avail my thyroid is still hyper but I keep gaining weight . I started phentermine a month ago and went on a 1360 calorie diet I just came back from the doctor and I gained 3! Pounds I also walk 2.5 miles a day and drink 110 ounces of water a day . What is going on why am I gaining weight. Very frustrated

  28. Hello everyone
    I started phentermine -Prozac 13 days ago 06.01.2017
    Stop taking Prozac about 3 days ago because I don\’t like the way it makes me feel .
    My concern is :
    On jun 01 I weighted 148 at dr\’s office
    Jun 02 :144
    Jun 03 :143
    And I have been on the same number 143 ever since
    Is there anything that I\’m doing wrong . Why isn\’t it working for me

  29. I have been on this med for 2 months and have lost 15 pounds. I\’m 5\’3 weighted 145 down to 130. I have so much energy, I started working out 4- 5 times a week for at least 1.5 – 2 hours. I\’be been moody and stress over little things.
    I walk a lot and eat less than 1500 calories a day. I had to purposefully increase from 1000 a day per my personal trainer (who have not idea I\’m taking this). But I haven\’t lost anything in about 2 -3 weeks now. I am not sure if I should continue or not. I would like to lose another 5 pounds and or go from 32% body fat to at least 26%.

  30. Sometimes there just is no answer and no hope. I\’ve been on phentermine for two months with no progress. I\’m spending 10-12 hours per week in the gym- working so hard that it often hurts to walk from sore muscles. I\’m following a strict, doctor ordered nutrition plan and forget about a cheat day… I haven\’t even had a cheat BITE. I\’ve been checked for all medical reasons that the weight is not coming off and there are no answers there, either. My vitamins and minerals are spot on. I am consuming a full gallon of water every day. Still nothing.

    I\’m trying to just be happy with the positive life changes I have made, hoping that they mean I\’m healthier, even if there is 0% chance of ever losing these pounds.

  31. I am on Phentermine as well, and am on week 3. My Doctor will only prescribe it for 3 months and said the normal amount of weight loss is about 2 lbs per week, sometimes more in the beginning. He recommended I use the slimfast diet along with the pills, and to only consume 1500 calories. I went out and bought the Aria scale from Fitbit, so I could know my numbers weekly. I haven\’t noticed any weight loss whatsoever. However, I have been sick twice in the past 3 weeks, so I have not been able to workout. For those of you working out daily, and eating properly, if you notice there is no weight loss, please remember that you are still burning calories and losing body fat, but you are gaining muscle weight! Muscle will weigh more than fat! It gets people down when they look at a scale since they see no shift in the number! Don\’t let this get to you! I do not like relying on a scale to tell me my weight, only using one now to keep track due to taking the Phentermine. If I feel better after working out and my clothes fit better, then I don\’t a scale to tell me an irrelevant number, and make me feel bad about myself. I am going to buy a bicycle this week so I can ride in the morning and evenings, and hope this will help me in my weight loss goals. I hope that you can all develop and maintain healthy habits, that\’s will stick with you for the rest of your lives, and hopefully inspire your loved ones as well! Many people around me are on the Keto Diet and love it. I am looking into it, just need the time and patience to cook such specific food! Good luck to everyone!

  32. Help!! I was prescribed 37.5 Phentermine not generic. I have not experienced any burst of energy, no appetite suppressant!! Am I not taking the right medication!! What do you recommend? My pills say K25!

    • Hi Paula!

      Have you consulted with your prescribing doctor? The only difference between generic phentermine and brand names are subtle differences, like additional flavoring, release method (longer or shorter times for body to process the drug, etc). IF you DO NOT feel the effects of the treatment, we urge you to contact your doctor for further assistance, as we are not qualified to give medical assessment.



  33. I was on 15 mg per day for three weeks, not one ounce came off. My doctor then prescribe 30 mg per day and I’ve done that now for a week and not one ounce has come off. I spend up to six hours per day as a professional housekeeper, I ride a horse twice a week, and do stretching and toning exercises in the morning. I take in about 1400 to 1500 cal per day which my doctor approved. I am on a ton of medication for thyroid, insulin resistance, high blood pressure, pain, neuropathy, it’s Cetera at Cetera. Not to mention I drink a Ton of water every day, And to get an average of seven hours of sleep per night. Why on earth is this medication not working for me?

    • Oh I am also on anti-depression and anti-anxiety medication Effexor.I went from 147 to 160 while on this medication. I am now holding at 158 pounds and it’s nerve-racking because I can’t seem to break this !

    • Dear Michelle,

      This is a question best asked to your prescribing doctor or a weight loss specialist. Thyroid conditions can greatly impact the weight loss process, and the amount of medication you are taking could be having additional effects, although no contraindication seems obvious at a glance.

      You -are- doing everything you should be doing. The medication is not working for you. You will need to consult with a professional to find any underlying causes for this.



  34. I started Phentremine capsules 15mg in Mid Feb. I started out at 248lbs at 5’6”. The first month I was extremely tired. (I also take topamax for chronic migraines so I had already cut out sodas for over 6 months). I assume I was really tired because I completely cut out all processed sugars and fast foods which put my body into withdraw. I still never got the boost of energy 2 1/2 months into take Phen. At my 1st weigh in, one month after being in Phen I weighed 235lbs. I lost about 13lbs. I also was not eating very well, meaning I was forgetting to eat and having tonforce my self to eat the first month. I ended up deciding to buy equate meal replacement shakes because my body was telling me, “ hey you’re hungry” by me starting to get a little confused or cranky. This way I would remember to A) drink a shake and b) you need to prepare a snack for later so you eat real food. The second month weigh in I weighed in at 226lbs. I was a little depressed. My target goal was 220lbs. However, it’s my own fault. I know I would’ve had better results if I had exercised. I did not exercise at all. As in maybe I burned 300 calories a day. I know I need to work on my exercising habits but the second month I was really focused on making healthier eating habits/choices and over coming cravings. Today I weighed myself on a different scale and it appears I have gone up 2 lbs. Which it has been 2 weeks since I did my last official weigh in. I have been more active and exercising more but my appetite isn’t really suppressed anymore. I don’t over eat but I am eating more than just 2 shakes a snack and dinner. I’ll have one shake in the morning and want a lunch and dinner and a snack after dinner. I have a feeling that my body is getting use to the appetite suppressant. That is really all I wanted the Phen for was for my appetite to be suppressed so I could retrain myself not to over indulge. I do fee that so far I am a lot more conscious about what I eat, how much of what I am eating, and I am able to say no to bad choices without giving in to temptation. If I walk away with with being 227lbs but with the will power and confidence that food doesn’t control me or emotions doesn’t control my eating habitats then Phen did what I ultimately needed it do.

  35. Also— would be nice if this thread started with he most recent (current) post instead of one that is from yeas ago. 🤗

    • Hi Amanda, this is a great suggestion – thank you! I will pass it along to our IT department 🙂
      Rachel, phentermine.com

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