Phentermine Contradications

• Patients with the following should not use Phentermine:
  • An allergy to any ingredient in Phentermine or other sympathomimetics (e.g., pseudoephedrine)
  • Are also taking dexfenfluramine, fenfluramine, furazolidone, guanadrel, guanethidine, or have taken a monoamine oxidase inhibitor (MAOI) (e.g., phenelzine, in the last 14 days
  • Have severe high blood pressure, an overactive thyroid, glaucoma, heart or blood vessel disease, or severe narrowing of the blood vessels
  • Are in an agitated state, or have a history of substance abuse
• Some medical conditions may interact with Phentermine, patients with the following should consult with their doctor before using phentermine:
  • Are pregnant, planning to become pregnant, or are breast-feeding
  • Are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • Have allergies to medicines, foods, or other substances
  • Have a brain or spinal cord disorder, hardening of the arteries, high blood pressure, diabetes, or high cholesterol or lipid levels
• Some medicines may interact with phentermine, such as the following:
  • Dexfenfluramine, fenfluramine, furazolidone, or MAOIs (e.g., phenelzine) because the risk of serious side effects, such as increasing headache, high blood pressure, slow heart rate, elevated temperature, or possibly fatal lung problems, may be increased
  • Guanadrel(Hylorel) or guanethidine(Ismelin) because their effectiveness may be decreased by phentermine
  • Antacids: Antacids may decrease the excretion of phentermine.
  • Carbonic anhydrase inhibitors (acetazolamide, dichlorphenamide, methazolamide): Carbonic anhydrase inhibitors may decrease the excretion of phentermine.