What You NEED To Know About Your Thyroid And Phentermine

What You NEED To Know About Your Thyroid And Phentermine

Weight loss is a struggle for many people, but when you have additional health problems to contend with, the journey to your goal weight can be even harder.

Phentermine is often a great solution for those who need to lose weight but have medical issues which also need to be addressed, as is the case for the many people who struggle with their weight as a result of an underactive thyroid, known as hypothyroidism.

To conclude this mystery topic, we will explain everything you need to know bout your thyroid and phentermine!

Hyperthyroidism & Hypothyroidism

The thyroid, a small gland found in the neck, acts as the control center for your body; hormones secreted by the thyroid help to maintain the brain, heart, muscles, and other organs and help the body to use energy properly.

So when something goes wrong, and the result is an underactive thyroid or overactive thyroid, your metabolism either revs up too high or slows right down.

These two conditions – hyperthyroidism and hypothyroidism – affect the thyroid differently and, therefore, have distinct symptoms.

Hyperthyroidism is an overactive thyroid, where the body makes too much thyroid hormone.

It can be thought of as your body’s system acting like a racing car engine, as all functions speed up and become difficult to control.

Hyperthyroidism is most often caused by the onset of Graves’ disease, which can result in the formation of a toxic swelling in the neck, called a goiter, protruding eyes, palpitations, sweating, diarrhea, weight loss, and muscle weakness.

Although sufferers experience weight loss, this is far from desirable as it results from fatigue, muscle weakness, and an unhealthy body.

The treatments often result in increased weakness and an inability to fight disease, which is why, in some cases, the thyroid is removed altogether.

Hypothyroidism is an underactive thyroid, whereby the body does not make enough thyroid hormone.

The most common cause of hypothyroidism is an autoimmune disease called Hashimoto’s disease.

In this condition, the immune system makes antibodies that destroy thyroid cells and stops them from making the thyroid hormone.

Hypothyroidism causes the whole body to slow down, including metabolism, heart rate, and digestive tract, meaning body functions are sluggish and difficult.

Symptoms of hypothyroidism include fatigue, dry hair, skin and nails, constipation, cramps, depression and weight gain.

Due to their slowed metabolic rate, people with hypothyroidism can feel that they are doing everything right as far as eating and exercising go but still struggle with weight gain, and if they’re trying to lose weight, rates can be painfully slow.

How Phentermine Helps Thyroid Problems

How Phentermine Helps Thyroid Problems

Despite the link between hypothyroidism and weight gain, doctors also propose that in some cases, if those with underactive thyroids actively forced themselves to maintain a normal activity level, they may only gain a few pounds.

Doctors explain that with many cases of weight gain resulting from hypothyroidism, due to symptoms such as depression and fatigue, sufferers are often too tired or lack the motivation to exercise and so fall into an unhealthy cycle of decreased activity and over-eating as an emotional outlet.  

Therefore, in addition to medications that normalize thyroid hormone levels, sufferers of hypothyroidism who need to lose weight could greatly benefit from taking weight loss medications, such as phentermine.

Sufferers of hypothyroidism are often prescribed Synthroid, which contains levothyroxine, a synthetic form of the thyroid hormone that allows the replacement of the thyroid hormone and, therefore, normal thyroid levels.

As a result of the normalization of thyroid levels, excess weight may be lost. However, Synthroid is not a weight loss medication, and therefore some sufferers may require additional help to lose excess weight.

By increasing energy levels and decreasing appetite, phentermine can help those with hypothyroidism with the additional symptoms that come as a result of an underactive thyroid, such as tiredness and lack of energy.

By encouraging sufferers to incorporate more exercise into their lives and to break the cycle of inactivity, depression, and emotional eating, phentermine could enable those with hypothyroidism to reach their goal weights and also experience an improved mood and better overall health.

Sufferers of hypothyroidism who are taking phentermine can also find lots of support in the phentermine.com support group on Facebook.

It is important to stress here that phentermine and Synthroid, or any other medications, may only be taken together if they are prescribed by a doctor who knows that the patient is taking this combination.

While many people report success with weight loss while taking phentermine and Synthroid, in some cases, it may be inadvisable for others to take both medications.

This is due to individual differences between patients, which could result in potentially harmful interactions for some people. Therefore, we would emphasize that the two should never be taken together without approval from your doctor.

In cases where hypothyroid patients cannot take phentermine but feel that they could benefit from additional help to lose excess weight, the weight loss supplement PhenQ provides an excellent alternative to phentermine.

PhenQ also boosts energy levels and reduces appetite, so those with hypothyroidism can benefit from these effects to help them be more active and eat better as part of a healthy lifestyle that can be maintained in the long term.

As with phentermine, we recommend that you consult your doctor before taking PhenQ if you are taking other medications. PhenQ has no known side effects and can be taken for as long as necessary, with your doctor’s approval.

Do you have hypothyroidism and struggle with your weight? Let us know your story by commenting below.

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  1. I have hypo thyroid issues and Hashimotos and I’m taking Adipex and it makes me sleepy about 30 minutes after I take it. I don’t take it every day because of this. What else can I do.

  2. Hi. I was prescribed Phentermine in the past (19 & 16 years ago) after I had each of my children, and it worked great. I am not what people would consider overweight (size 4-6), but I have always watched what I eat (my teens call it “birdseed”) and exercised 4-5 times a week (2 x Bikram yoga for the past 20 years, 3 x treadmill intervals for an hour with about 18 minutes of running, I have a old torn ACL). I am going through menopause/perimenopause and at the same time was diagnosed with low thyroid so am just gaining weight and feel miserable because I felt there was nothing more I could do, just pushing myself. Dr did a full panel (all my vitamin levels are good), and I started Phen (37.5) and a low dose of Synthroid (25?) this week. I am booting up my exercise to 6 times a week (still 2 x Bikram yoga + 3 x Barry’s Bootcamp + 1 x 1-2 hour treadmill walk). I am eating less, just trying to be conscious of everything (writing it all down) and trying to choose only the healthiest foods (Greek yogurt, fruits, veggies, eggs, fish, very lean meat, and these small gluten free banana-carrot muffins I bake with no butter/oil and sweetened with agave). I cut out gluten a year ago, now am eliminating soy, and I never ate things like pasta or white rice (haven’t had junk or fast food since about 1987) I really hope this works, because my old clothes don’t fit at all and some newer pieces are getting very tight (I was a 2-4) and I can’t imagine anything else I can do.

    1. Hi BB,

      Thank you for sharing. We wish you the best of luck in your journey. You are also more than welcome to join our official Facebook support group so you can connect with other phentermine users today: https://www.facebook.com/groups/1069871763087734

      Best regards,

      Sarah, Phentermine.com

  3. I am having my thyroid removed this week and wondering if phentermine will still be effective post thyroidectomy?

    1. Hi Vicky,

      Unfortunately, we are not qualified to answer that. Please consult with your prescribing doctor.

      We wish you the best of luck!

      Sally, Phentermine.com

  4. Hi, my name is Kim and I have just been diagnosed with hyperthyroidism . I have been taking phentermine for about 5 months the dose is 37.5. My question is did phentermine cause my hyperthyroidism and should I stop taking it or can a lower dose of phentermine be a better option?

    1. Kim,
      Did you ever find an answer to this? I have been taking Phentermine for about 6 months and am wondering the same thing…

  5. I am female and weight 216. I have had hypothyroidism for over 25 years and take Synthroid. I had liver enzyme issues due to medication, Zolof, 20 years ago. After stopping Zolof, liver tests results returned to normal, I had a liver biopsy which showed fatty liver, but I have had no problems since. I was diagnoised with Rheumatoid Arthritis 13 years ago and presently take an IV Infusion therapy medication, Simponi. On a regular basis, my RA doctor has lab tests done on my liver and I have had no issues. Does Phentermine have any properties that Zolof has? If the answer is no, then could I successfully take Phentermine in conjuction with my other meds?

    1. Hi Valerie, thanks for your comment! We would suggest posing this question to your personal doctor(s) and pharmacist. Unfortunately we are not qualified to provide specific medical or pharmaceutical advice.
      Rachel, phentermine.com

  6. I can totally vouch for this. I was diagnosed with hypothyroidism about 8 years ago and my weight has climbed ever since. It didn’t matter what I did. I tried to tell my doc but she never seem to understand. I got really discouraged. Finally, I decided to see a bioidentical hormone therapy doctor. I went to see him at the end of February. After some lab work, he added some T3 and put me on Phentermine 37 but only half of a pill. Adjusted my diet, workouts and I had to eliminate any caffeine. Also added vitamin D that I was deficient in as well. I am now down 60lbs and still loosing. I feel 100% better. I haven’t had any heart palpitations( which I actually did before seeing him.) I have been so happy with the results!

    1. Thanks for sharing your experience Sommer, and BIG CONGRATULATIONS on your success so far!! Keep up the great work 🙂
      Rachel, phentermine.com

  7. Hello,

    I have hypothyroidism and have been taking pherntermine 37.5 for four months now. I have been able to lose 25 pounds and im considering taking Phen caps. Has anyone with hypothyrodism taken phen caps? Was there any side effects with your synthroid.

  8. Great article. I have an aunt recently diagnosed with sever under-active thyroid and so I am researching more natural treatment options. Thanks for sharing.

  9. I have had hypothyroidism for many years now. I just started taking phentermine 37.5mg. I am unsure if I should take them both in morning on empty stomach. My doctor didn’t say. Does anyone else take levothyroxine 50mg and there phen at same time???

    1. I take levothyroxine 1/2 hour before I eat breakfast. I have breakfast and an hour later take phentomine. That is what the doctor told me and I feel good.

    2. I also take levothyroxine and phentermine. The way that I was instructed to take it was to take my levothyroxine 1 hour before breakfast and then take the phentermine with a very light breakfast. It works very well for me and I have been very successful with weight loss.

  10. I have hyper and hypo thyroidism. I was first diagnosed with hyperthyroidism and I was skinny. Then I was diagnosed with hypothyroidism. Slowly I began to gain weight with the help of steroids and other things. In February the Dr placed me on 15mg of Phentermine. In June I think it was I was increased to 30mg of Phentermine. I am now trying to wein myself of of the medication. I have not lost any weight while being on this medication. I have gained like 80lbs since being on this medicine; so why continue to take it. Has anyone had the same issue as I have? I have definitely got to loose some weight. I do not over eat. I even started eating really healthy and still no positive results.

  11. I was diagnosed many yrs ago with underactive thyroids an I also have ostio arthritis in all my joints I find it pretty hard to walk to far witout having pain I put alot of this down to my weight I an 5ft 4 an my weight is around 14 stone having underactive thyroids is a struggle on its own I waa hoping that I will b allowed to take the phentermine along side my other medication im also on zapain which contains codeine an paracetamol for the pain from ostio arthritis could anyone plz advice me on this I do not wish to take any other medication before checking if this is ok to do so thank you.

    1. Hi Carole! Thanks for your comment. Unfortunately we are not qualified to dispense specific medical or pharmaceutical advice. We would recommend speaking with your doctor and pharmacist about your interest in phentermine alongside your current medications. They are best suited to advise you on the appropriateness of this weight loss medication in your specific case. Best regards!
      Rachel, phentermine.com

  12. I have hashimotos and I’ve been on phentermine since the middle of May. I’m 58 and have lost 30 pounds almost. I weighed 216 and I’m down to 187. How? I am doing intermittent fasting and it’s revolutionized my body.

    1. Debbie
      Hi how are you?
      Wow that sounds amazing. What dosage of phentermine were or are you on? Do you think you will be on it for life? Are your thyroid homones levels ok? Do you feel any better with weight loss? Have you lowered or changed thyroid hormone medication? Was intermittent fasting approved by a doctor? I read about lack of nutrient diffieciency and disgestive gut enzymes help the productivity of thyroid gland! Have you started intake of better foods?
      I pray you are well!

  13. Although Phentermine can assist in some weight loss as a hypothyroid patient, I can personally say it isn’t the best solution. I was on this drug for a few months before my wedding, and it helped in losing only a few pounds. Although that was nice, it’s not a drug you can take long term because as a stimulant it can cause heart problems. I noticed I had heart racing on this drug many times while taking it. Secondly, being a stimulant, it acts very similar to ADD stimulant drugs, and as another nice side effect you become laser focused. The problem I ended up with after I went off this drug is I had concentration issues for quite some time. At one point my primary care physician has to start prescribing Vyvanse because Phentermine caused my brain to have a dependence on the stimulants over time.

    It sounds like a great solution, but coming from someone whose has had Hypothyroid for almost 35 years, spent my whole life from 7days old onward on synthroid, and struggled with weight issues my entire life, Phentermine isn’t worth it. It’s a short term fix for long term lifestyle changes that are needed to better correct the issue. My biggest success with weight loss as a Hypothyroid patient was moderate exercise and a high protein and low carb diet. Worked better than this drug ever did. ☺️

  14. I am hypothyroid and was taking Levothyroxin and Phentermine but only for a few weeks. I did delelope an irregular heart rate PVC’c and shortness of breath. My doctor reduced the Thyroid medication from 100 down to 88 mg and took me off the Phentermine. Because I lost weight I needed less thyroid medication. The side effect for too much thyroid meds or a side effect for the Phentermine can be irregular heart rate. If you are taking both be sure your doctor checks your blood work if you feel different – more tired or just not like yourself have things check out! Had found irregular heartbeat on blood press cuff. Dr heard it in office – then saw PVC’s on EKG.

  15. Yea I have hypothyroidism and in the pass 4 years I have gone from size 5 to size 12 and have tried to lose weight, and I’m struggling to lose weight…I’ve tried everything and nothing has worked…don’t know what to do any more….I don’t like myself anymore…

    1. Hello Judy. Thank you for reaching out.

      As well as being an appetite suppressant, phentermine boosts energy levels to help you get on track with leading a more active lifestyle. But not everyone experiences the same energy boost with phentermine, so here we have ten tips to get more energy from phentermine, making it easier to see results now and in the long term: Get more energy with Phentermine.

      Hope that helps! Also, 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/

      Rebeca, Phentermine.com

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