Phentermine FAQs

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Phentermine Dosage & Precautions

Who should not take phentermine?

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Phentermine should not be taken by anyone under 18. You should also not take phentermine if you are pregnant, nursing, or if you intend to become pregnant.

If you suffer from any of the conditions listed below, your doctor may decide that you are not a suitable candidate for phentermine as it may do you more harm than good. Taking phentermine may react with drugs that you have recently taken or worsen an existing health problem.

Phentermine contraindications

Prior to taking phentermine, it is very important that you tell your doctor if you have any of the following:

  • Allergy to phentermine hydrochloride, any of the inactive ingredients in phentermine or other sympathomimetic drugs
  • High blood pressure (Hypertension)
  • Cardiovascular disease
  • Diabetes
  • Overactive thyroid (Hyperthyroidism)
  • Glaucoma
  • A history of alcohol or other drug abuse
  • A history of suffering from an agitated state

Phentermine can interact with other medications. Be sure to inform your doctor if you are currently using or have recently used any other prescription or non-prescription medications. Harmful interactions can occur in some cases, so you may not be prescribed phentermine if you have taken the drugs listed below:

  • Any MAO inhibitor in the last 14 days. Examples of these powerful antidepressants include; Isocarboxazid (Marplan®), Mabanazine (Actomol®), Nialamide (Niamid®), Phenelzine (Nardil®)
  • Any other weight loss medications, both prescription and non-prescription