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Phentermine tablets or capsules

What is this medicine?

PHENTERMINE (FEN ter meen) decreases your appetite. It is used with a reduced calorie diet and exercise to help you lose weight.

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take it more often than directed. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children 17 years or older for selected conditions, precautions do apply.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

  • breathing problems

  • changes in emotions or moods

  • changes in vision

  • chest pain or chest tightness

  • fast, irregular heartbeat

  • feeling faint or lightheaded

  • increased blood pressure

  • irritable

  • restlessness

  • tremors

  • seizures

  • signs and symptoms of a stroke like changes in vision; confusion; trouble speaking or understanding; severe headaches; sudden numbness or weakness of the face, arm or leg; trouble walking; dizziness; loss of balance or coordination

  • unusually weak or tired

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • changes in taste

  • constipation or diarrhea

  • dizziness

  • dry mouth

  • headache

  • trouble sleeping

  • upset stomach

What may interact with this medicine?

Do not take this medicine with any of the following medications:

  • MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate

This medicine may also interact with the following medications:

  • alcohol

  • certain medicines for depression, anxiety, or psychotic disorders

  • certain medicines for high blood pressure

  • linezolid

  • medicines for colds or breathing difficulties like pseudoephedrine or phenylephrine

  • medicines for diabetes

  • sibutramine

  • stimulant medicines for attention disorders, weight loss, or to stay awake

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

Where should I keep my medicine?

Keep out of the reach of children. This medicine can be abused. Keep your medicine in a safe place to protect it from theft. Do not share this medicine with anyone. Selling or giving away this medicine is dangerous and against the law.

This medicine may cause harm and death if it is taken by other adults, children, or pets. Return medicine that has not been used to an official disposal site. Contact the DEA at 1-800-882-9539 or your city/county government to find a site. If you cannot return the medicine, mix any unused medicine with a substance like cat litter or coffee grounds. Then throw the medicine away in a sealed container like a sealed bag or coffee can with a lid. Do not use the medicine after the expiration date.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Keep container tightly closed.

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

They need to know if you have any of these conditions:

  • agitation or nervousness

  • diabetes

  • glaucoma

  • heart disease

  • high blood pressure

  • history of drug abuse or addiction

  • history of stroke

  • kidney disease

  • lung disease called Primary Pulmonary Hypertension (PPH)

  • taken an MAOI like Carbex, Eldepryl, Marplan, Nardil, or Parnate in last 14 days

  • taking stimulant medicines for attention disorders, weight loss, or to stay awake

  • thyroid disease

  • an unusual or allergic reaction to phentermine, other medicines, foods, dyes, or preservatives

  • pregnant or trying to get pregnant

  • breast-feeding

What should I watch for while using this medicine?

Visit your doctor or health care provider for regular checks on your progress.

Do not stop taking except on your health care provider's advice. You may develop a severe reaction. Your health care provider will tell you how much medicine to take.

Do not take this medicine close to bedtime. It may prevent you from sleeping.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may increase dizziness and drowsiness. Avoid alcoholic drinks.

This medicine may affect blood sugar levels. Ask your healthcare provider if changes in diet or medicines are needed if you have diabetes.

Women should inform their health care provider if they wish to become pregnant or think they might be pregnant. Losing weight while pregnant is not advised and may cause harm to the unborn child. Talk to your health care provider for more information.

NOTE:This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider. Copyright© 2020 Elsevier
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