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.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Ionamin, Pro-Fast
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
- 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
How should I use this medicine?
Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. This medicine is usually taken before breakfast or at least 10 to 14 hours before going to bed. Avoid taking this medicine in the evening. It may interfere with sleep. Swallow whole. Do not open or chew the capsules. Take your doses at regular intervals. Do not take your medicine more often than directed.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
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.
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
- medicines for colds or breathing difficulties like pseudoephedrine or phenylephrine
- stimulant medicines for attention disorders, weight loss, or to stay awake
This medicine may also interact with the following medications:
- certain medicines for depression, anxiety, or psychotic disturbances
- medicines for diabetes
- medicines for high blood pressure
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medicine?
Notify your physician immediately if you become short of breath while doing your normal activities.
Do not take this medicine within 6 hours of bedtime. It can keep you from getting to sleep. Avoid drinks that contain caffeine and try to stick to a regular bedtime every night.
This medicine was intended to be used in addition to a healthy diet and exercise. The best results are achieved this way. This medicine is only indicated for short-term use. Eventually your weight loss may level out. At that point, the drug will only help you maintain your new weight. Do not increase or in any way change your dose without consulting your doctor.
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.
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 vision
- chest pain or chest tightness
- depressed mood or other mood changes
- hallucinations, loss of contact with reality
- fast, irregular heartbeat
- increased blood pressure
- nervousness or restlessness
- painful urination
- trouble sleeping
- 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):
- constipation or diarrhea
- dry mouth
- stomach upset
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
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 accidental overdose and death if taken by other adults, children, or pets. 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 a 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.
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.
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