Phentermine, Oral

What are other names for this medicine?

Type of medicine: appetite suppressant

Generic and brand names: phentermine, oral; Adipex-P; Anoxine-AM; Dapex-37.5; Fastin; Ionamin-15; Ionamin-30; Obe-Nix 30; Obephen; Obermine; Obestin-30; Phentrol; Phentrol 2; Phentrol 4; Phentrol 5

What is this medicine used for?

This medicine is taken by mouth to control your appetite. Along with a sensible diet and exercise plan, it can help you lose weight.

What should my health care provider know before I take this medicine?

Before taking this medicine, tell your health care provider if you have ever had:

• a seizure disorder such as epilepsy
• an allergic reaction to any medicine
• depression
• diabetes
• glaucoma
• heart problems or high blood pressure
• kidney disease
• thyroid disease.

Females of childbearing age: Tell your health care provider if you are pregnant or plan to become pregnant. Do not breast-feed while taking this medicine without your health care provider's approval.

How do I take it?

Take this medicine exactly as your health care provider prescribes. It may be habit-forming. Use it only as directed by your health care provider. Do not increase the dosage without your health care provider's approval.

Take this medicine on an empty stomach 1 hour before a meal.

Some forms of this medicine are long-acting and must be swallowed whole. Ask your health care provider or pharmacist if this applies to your medicine.

If you miss a dose, take it as soon as you remember unless it is almost time for the next scheduled dose. In that case, skip the missed dose and take the next one as directed. Do not take double doses. If you are not sure of what to do if you miss a dose, or if you miss more than one dose, contact your health care provider.

What should I watch out for?

This medicine should be used only for short-term weight control. Follow your health care provider's advice about diet, eating habits, and exercise to maintain weight loss.

If you have diabetes, your dosage of insulin or other diabetes medicine may need to be changed when taking this medicine because you will be eating fewer calories.

This medicine may make you overexcited or cause trouble sleeping. Ask your health care provider or pharmacist when you should take the last dose of the day to avoid trouble sleeping at night.

This medicine may make you dizzy, drowsy, or lightheaded. Do not drive or operate machinery unless you are fully alert.

If you need emergency care, surgery, or dental work, tell the health care provider or dentist you are taking this medicine.

Avoid alcohol and caffeine while taking this medicine.

What are the possible side effects?

Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your health care provider if you have any side effects that continue or get worse.

Serious (report these to your health care provider right away): Fast heartbeat, chest pain, high blood pressure, inability to urinate, confusion, depression, rash, or hives.

Other: Nervousness, restlessness, trouble sleeping, irritability, constipation.

What products might interact with this medicine?

When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods may also interact. Using these products together might cause harmful side effects. Talk to your health care provider if you are taking:

• alcohol
• caffeine
• furazolidone (Furoxone)
• insulin and medicines taken by mouth to treat diabetes
• MAO inhibitor antidepressants such as phenelzine (Nardil), tranylcypromine (Parnate), and isocarboxazid (Marplan) (Do not take this medicine and an MAO inhibitor within 14 days of each other.)
• medicines used to lower and control high blood pressure such as prazosin (Minipress), doxazosin (Cardura), benazepril (Lotensin), captopril (Capoten), enalapril (Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), quinapril (Accupril), ramipril (Altace), diltiazem (Cardizem, Dilacor, Tiamate, Tiazac), nicardipine (Cardene), nifedipine (Procardia, Adalat), isradipine (DynaCirc), felodipine (Plendil), amlodipine (Norvasc), verapamil (Calan, Isoptin, Verelan), atenolol (Tenormin), acebutolol (Sectral), betaxolol (Kerlone), carteolol (Cartrol), bisoprolol (Zebeta), pindolol (Visken), metoprolol (Lopressor, Toprol XL), timolol (Blocadren), sotalol (Betapace), nadolol (Corgard), propranolol (Inderal), labetalol (Normodyne, Trandate), and carvedilol (Coreg)
• pseudoephedrine (an ingredient in many nonprescription cold remedies such as Sudafed
• selective serotonin reuptake inhibitors (SSRI) such as citalopram (Celexa), fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft)
• selegiline (Eldepryl)
• sibutramine (Meridia)
• tricyclic antidepressants such as amitriptyline (Elavil), nortriptyline (Aventyl, Pamelor), imipramine (Tofranil), and doxepin (Sinequan).

Keep a list of all your medicines (prescription, nonprescription, supplements, natural remedies, and vitamins) with you. Be sure that you tell all health care providers who treat you about all the products you are taking.

How should I store this medicine?

Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.

This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your health care provider or pharmacist for more information or if you have any questions.

Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.

Keep all medicines out of the reach of children.

Do not share medicines with other people.