Prescription onlyLower-cost generic available

Adipex-P

(Phentermine)

  • Pill
  • Extended release capsule
  • Dissolving tablet
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Makes you less hungry.

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Prescription onlyLower-cost generic available

Our pharmacists’ bottom line

Adipex-P (Phentermine) can help you lose weight, but most insurance companies don't cover it, and you shouldn't use it long-term.

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Works well?Does it work?
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  • Lowers appetite.
  • Can increase your ability to exercise and how long you're able to exercise.
  • Available as a combo with topiramate as Qsymia, which is recommended more highly, but it's still not that effective.
  • Even though Adipex-P (Phentermine) is available as a generic, most insurance companies don't cover it, so you may have to pay for it out of pocket.
  • Can lower your sex drive.
  • Can only be used for 12 weeks since you can develop tolerance.
  • Not a first-line treatment for losing weight.
  • Can be habit-forming.

Save on your next Adipex-P (Phentermine) prescription

Be sure you’re getting the lowest price for your medication, even if you have insurance.

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Side effects for Adipex-P (Phentermine)

Manufacturers don’t say how common these side effects are

  • Abnormally fast heart beat
  • Changes in libido
  • Constipation
  • Diarrhea
  • Dizziness
  • Dry mouth
  • Elevation of blood pressure
  • Euphoria
  • Headache
  • Heart pounding or racing sensation
  • Hives
  • Impotence
  • Intense emotional discomfort
  • Other gastrointestinal disturbances
  • Overstimulation
  • Primary pulmonary hypertension and/or regurgitant cardiac valvular disease
  • Rarely psychotic episodes
  • Restlessness
  • Sleep difficulty
  • Tremor
  • Unpleasant taste

What to expect when you take Adipex-P (Phentermine) for Appetite suppressant

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Tips from our pharmacists
  • This should only be used for a few weeks to help you lose weight along with diet and exercise.
  • You can feel dizzy the first few days you take it, so be careful driving or doing anything where you need to focus.
  • Take it early in the day so you don't have problems sleeping.
  • Take this before or 1 to 2 hours after your breakfast.

Risks and Warnings for Adipex-P (Phentermine)

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  • People on Adipex-P (Phentermine) have reported high blood pressure in the lungs. This has been very rare. Symptoms include trouble breathing, chest pain, swelling in your legs, and fainting spells. If you notice a sudden decrease in how much you can exercise, talk to your doctor immediately.

Means that some groups have a high risk of experiencing this side effect

Tips from pharmacists and people taking Adipex-P (Phentermine)

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The FDA category for this medication is X. It is advised that you: Unsafe
Pregnancy
Food
  • Tips from our pharmacists
  • Take this before or 1 to 2 hours after your breakfast.
Sex
  • Upsides and downsides from our pharmacists
  • Can lower your sex drive.
  • Risks from our pharmacists
  • Adipex-P (Phentermine) can cause changes in your sex drive, including impotence in men. Talk to your doctor if this bothers you.
Sleep
  • Tips from our pharmacists
  • Take it early in the day so you don't have problems sleeping.
  • Taking it in the morning is less disruptive to sleep patterns than taking it later in the day, but still an issue.
    Taken for: Overweight
    Duration taken: A few months
  • Helped me lose 30 pounds in a couple months. I had a hard time sleeping tho
    Age: 21
    Gender: Woman
    Taken for: Obesity (short-term treatment)
Weight gain or loss
  • Upsides and downsides from our pharmacists
  • Not a first-line treatment for losing weight.
  • Tips from our pharmacists
  • This should only be used for a few weeks to help you lose weight along with diet and exercise.
  • Risks from our pharmacists
  • Taking Adipex-P (Phentermine) for weight loss is only meant for a few weeks at the most, since your body can become used to the medication, and then it stops working. Taking more than what your doctor tells you to take will not help. Talk to your doctor about how to use this to help you lose weight along with diet and exercise.
  • I wasn't obese, but helped maintain a good weight and gave me energy.
    Age: 51
    Gender: Woman
    Taken for: Obesity (short-term treatment)