Why You're Not Losing Weight With Phentermine

Why You’re Not Losing Weight With Phentermine

Phentermine is undoubtedly an extremely effective weight loss medication.

Still, for all of those who experience weight loss success, some 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 know 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 weighing it out afterward.

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.

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2. Not Eating Enough

Phentermine works by suppressing appetite, but sometimes this effect can be too strong, to the extent that people have zero appetites 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.

Still, 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 prioritize sleep 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 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.

As a result, losing weight with phentermine is more difficult. So, ensure you get the recommended daily requirements of important weight loss nutrients for better results.

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 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 cannot exercise due to injury, you should get moving every day, even if it’s just walking for half an hour.

Exercise is a great stress reliever, and 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.

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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 the best from your diet by seeking out foods packed with vitamins, minerals, and healthy fats, avoiding anything overly processed and filling up 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.

Still, 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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  1. Heya,
    What is the recommendation for someone when the duromine has stopped working?
    Iv been taking for over a month, I lost just under 10 kg and now nothing more. Staying at the same weight.
    Should I take a big break from taking the remaining months, and then trying again to see if it starts working or something else?
    I got the impression that duromine would suppress my appetite but also help me loose weight without having to do much exercise.

    1. Hi George,

      If Duromine isn’t working for you anymore, your doctor might suggest alternative medications or weight loss strategies. There are other prescription medications, as well as non-prescription options and lifestyle changes, that can support weight loss.

      Taking a break from Duromine might be beneficial. Your body can build up tolerance to the medication over time, reducing its effectiveness. A break could help reset your body’s response to the medication.

      Sally, Phentermine.com

  2. Heya,
    What is the recommendation for someone when the duromine has stopped working?
    Iv been taking for over a month, I lost just under 10 kg and now nothing more. Staying at the same weight.
    Should I take a big break from taking the remaining months, and then trying again to see if it starts working or something else?
    I got the impression that duromine would suppress my appetite but also help me loose weight without having to do much exercise.

  3. Hi, I started Phentermine two months. The first two weeks I lost 9 lbs. Starting weight 174 lbs went down to 165. After that, I haven’t lost anymore weight. Instead I go up and down from 165 to 168. My appetite has stayed low but not as low as when I started. I would like to go down to 150 if possible, but I’m stuck in the upper 160s. Any suggestions

    1. Hi Mosquito,

      It’s not uncommon to experience a weight loss plateau after the initial rapid loss. Your body might have adjusted to the medication, and its effectiveness in suppressing your appetite might have decreased. This is why your weight loss has slowed down.

      To break through a plateau, consider making changes to your diet and exercise routine. Ensure you are eating a balanced diet with a calorie deficit (consuming fewer calories than you burn). Incorporate more fruits, vegetables, lean proteins, and whole grains into your meals. Also, try to increase your physical activity level. Find more tips from us here: https://www.phentermine.com/phentermine-stopped-working/

      You are also more than welcome to join our official Facebook support group so you can share your experience with other phentermine users and get feedback on your particular situation: https://www.facebook.com/groups/1069871763087734

      Sally, Phentermine.com

  4. In the past ive used duromine. Duromine suppressed my appetite a lot and I never felt hungry will on those pills.
    This time. The doctor said phentermine is the same as duromine but without the price tag that now comes with duromine (phen is roughly $30 cheaper). So I opted for phentermine. I get the dry mouth and sometimes the lack of sleep but im hungry. My stomach is giving me so much grief being hungry. When I eat food the taste is so much stronger and flavoursome and I want to keep eating. That should not be happening on phen. Definitely didnt happen on duro.
    Its almost like its making me more hungry than when I wasnt on them. So im just bearing the constant pain of hunger.
    Wouldve been better off with duromine.

  5. Hi,
    I’m desperate. Phentermine worked very well for me in the past but I haven’t lost anything this time.
    Please help!!

  6. Hi week 3 on duramine.30 mg have lost 5.5 kgs but am now at a standstill.i was 91 kg now 85.5 kg and have seemed to come to a stand still at 85.5.maybe not enough water and I went off my vitamins. I take 4 women’s vita gummies a day and 2 vitamin b.s. as I’m low in vit b.my diet is good.salad yogurt fruit 2 multi grains slices bread per day and lean cuisine frozen prepared meal for dinner.and only water and a 1 cup of tea in morning with 1 sugar tablet what do u think of that .thanku fiona

  7. Hi I’m 30 years old, 5’4, and I weigh about 197 lbs. I started phentermine about two weeks ago. Dr adviced me to take half a pill the first week but when I notice that I hadn’t lost anything I went back and asked him to up my dose, he told me to go ahead and take the whole pill which is 37.5 mg. I’m on the second week and still see no weight loss yet. The appetite has decreased somewhat and I’ve been trying to eat lots of chicken and salads instead of the junk I was eating before. I must also say that I have high blood pressure and take Metoprolol twice a day. I also take tramadol 150mg 3 times a day because I’m addicted to it and dr is slowly weaning me off of tramadol, I used to take a whole lot more a few months ago and I’ve been addicted to it for about 10 years but recently I decided that I wanted to stop taking it for good.
    Anyways, I was also told by my dr that I’m very low on vitamin d. Could any of these be the reason why I’m not losing weight?? I have an appointment with my dr tomorrow to begin a weight loss program where they give you a shot twice a week, this shot is a fat burner with vitamin B12 and lipozene.
    They also give you a seven day supply of phentermine (which I already have) and a seven day supply of topamax. Will any of this help me lose weight any time soon?

    1. Hi Isa,

      In an effort to make phentermine work better, many patients look for supplements to take with phentermine. Learn more here: https://www.phentermine.com/phentermine-stopped-working/best-supplements-phentermine/

      Over time, the body adapts to phentermine and its effectiveness can decrease. Phentermine tolerance is an especially common problem for patients who have taken phentermine for a long time, or are taking it for the second or third time. Here we explain more: https://www.phentermine.com/phentermine-stopped-working/

      Hope that helps!

      Rebeca, Phentermine.com

      1. Hi. I’m on my third day of phentermine. I’m 20, male. The issue isn’t that I need faster results, I’m patient, the issue is that phentermine doesn’t give me energy, even though it’s a stimulant. in fact, it makes me tired and sluggish, but it does make me feel content and calm. This is a little concerning for me, as it’s the opposite of what I’m supposed to be feeling . Some doctors think I have ADD, others said I do not, so I’m wondering if it’s just that I have ADD and so phentermine is having a sedating effect on me. It’s just a little concerning to me, and I haven’t seen anyone else have this problem.

        1. Hi Silas,

          Thank you for reaching out. About 1 in 5 users report experiencing phentermine fatigue. While severity, duration and cause varies between patients, there are several common explanations for why phentermine makes you sleepy: https://www.phentermine.com/phentermine-side-effects/fatigue/

          Also, here are a few tips that might help you boost your phentermine: https://www.phentermine.com/phentermine-stopped-working/

          Best regards,

          Rebeca, Phentermine.com

  8. Hi
    I have been on Duromine for 2 weeks now , 15mg , nothing is happening at all , actually just putting on more weight. I am 52yo , in full menopause !!!
    help i am so frustrated and disappointed !

  9. Hi. I’ve been on phentermine 30mg for 8 weeks. Lost 12lbs total. I eat right, drink my water, exercise every day. They added amino acids, B12 and chromium. They upped my dosage to 37.5mg to see if that would help but doesn’t. In 4 days, i gained and haven’t changed anything. I am also post menopausal. Does Phentermine help us that are older? I have alot to lose.

  10. Hi I got phentermine from a doctor and 6 days in I started craving bad foods again and wanting to binge as if the phentermine lost its touch. There is no way I built up a tolerance in 6 days that’s nuts! Help!

  11. I have been on Phentermine for 11 months now and when I first started I was all excited I was down 11 lbs. But I haven’t lost since but I haven’t gained anything either. This is very upsetting. I feel like I hit a wall. I can tell that the Phentermine is working just not in the weight loss area. I don’t know what to do.

  12. I started Phen last week after my weight has really gone up in the past several years. My ideal weight is 120-125. I’m 151 lbs.now. 5’5 and 65 y.o. Even though I eat fresh vegs, fish & chicken, and little carbs, I keep gaining, Asked my doc to recommend something to jump start my metabolism. She prescribed Phentermine 37.5. After 4 days of the jitters, dizziness, dry mouth and headaches, I havent lost an ounce! It’s very discouraging to read these comment from Phen users who are religiously counting calories, exercising hours a day, eliminating carbs, giving up coffee, teas & soda, and still little to no weight loss! AND, if the AVERAGE monthly weight loss (as determined by several medical studies), is ONLY 3-6 lbs, why bother taking Phen? The cost ($40 for 30:pills) & side effects just aren’t worth the minimal (or no) results. VERY DISAPPOINTING.

    1. Maura, I took Phentermine a few years back and went from 150 lbs to 119lbs, size 12 to size 4. Here’s what I did: When starting out taking Phentermine, take 1/2 a tablet for the first week, then increase to a full tablet, this helps your body adjust to it and jitters and dizziness go away. The dry mouth helped me drink more water, it was irritating but I kept taking the pills, the first month I only lost 3lbs, doctor said keep trying. I was exercising some, eating more chicken and fish, fruits and veggies but still not losing. I went back after another month and again I had only lost 2-3 lbs, again he suggested to keep trying. So I did. The third month, I changed nothing, still exercising a little, still eating the same, changed nothing I had done the 2 previous months. After my first week into the 3rd month I started dropping weight and dropping it fast. I lost all my weight within 5-6 months. I think everyone’s body chemistry is different and some start losing right away and others take a little more time. Oh and only weigh yourself once a month, your weight can fluctuate during this time and can be very frustrating. If you try again, Good luck, drink lot’s of water, take vitamins, walk, eat better.

    2. I having same problem.. started on mid range dose. 30 days lost 5 pounds. Now on 37.5, no jitters or bad side effects, except still not losing weight. started at 203, 60 days later 196. walk minimum of 2.5 miles a day. even if I didn’t walk a d count calories I should of lost atleast 20 pounds. so disappointed. I’m 67″ and 46.

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