09-10-2020 Your prescriptions

Is Phentermine Safe for Weight Loss?

Is Phentermine Safe for Weight Loss? | America's Pharmacy

The journey to weight loss can be long and frustrating for some. From trendy diets to new workout fads, finding what works best for you and your body takes time, commitment and in some cases, a collaborative effort with your physician. For those who seek help from their physician to kick start weight loss may come across the prescription, Phentermine. Is this prescription safe? Is Phentermine effective? We’ve got everything you need to know about Phentermine and if the weight loss drug could be right for you.

What is Phentermine?

Similar to amphetamine, Phentermine is a prescription medication used for appetite suppression when paired with a weight loss plan. As one of the most common weight loss prescriptions, Phentermine has been prescribed since the early 1970’s. Can’t seem to control your appetite? Phentermine mimics the sensation of feeling full, leading to curbing your appetite. Patients with Binge Eating Disorder and Bulimia Nervosa have also seen positive results with reducing the instances of binge eating episodes by taking Phentermine.1

Is Phentermine Safe to Take?

Phentermine often gets mixed up with fenfluramine, and the dangerous but popular mixture of “Fen-Phen” in the 90’s. Patients taking both fenfluramine and Phentermine began to experience heart valve disease and pulmonary hypertension, in which the FDA immediately recommended patients discontinue taking fenfluramine. Luckily, these reports were not caused by Phentermine, and is generally safe to take when prescribed by a physician. Like all prescriptions, you should always discuss the risks of prescriptions with your physician.

Who Does Phentermine Negatively Affect?

So, if there are risks and side effects, what are they? Phentermine does have the potential to become an addictive or abused drug and should be taken with extreme care. For those who have previously or are currently struggling with drug abuse, Phentermine may not be the right weight loss solution. While usually mild and uncommon, side effects of Phentermine include:2 

  • Increased heart rate
  • Tingling or prickling feeling in hands or feet
  • Dry mouth
  • Sleeplessness
  • Nervousness
  • Constipation

Weight loss during pregnancy can be harmful to an unborn baby, so pregnant and nursing mothers should not take Phentermine. People with heart issues such as high blood pressure or heart disease should seek out alternative weight loss solutions as well due to these side effects.3

How Much Weight Can I Expect to Lose?

Clinical studies have shown patients using Phentermine to see a 5% weight loss of their starting weight, while in some cases, seeing weight loss as high as 10% of their starting weight.2 It’s important to keep expectations low, and not expect the weight to fall off within the first week. Phentermine can take between 12-16 weeks to see significant weight loss results.

Only Under a Doctor's Supervision

Phentermine is a prescription drug and must be used only when directed to do so by a doctor. A patient should never use Phentermine unless under a doctor’s supervision.

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1. https://www.mayoclinic.org/healthy-lifestyle/weight-loss/expert-answers/phentermine/faq-20057940

2. https://www.healthline.com/nutrition/phentermine-weight-loss#weight-loss

3. https://www.drugs.com/phentermine.html