What is this medicine?

CAFFEINE (KAF een) is a stimulant. It is used to increase mental alertness or wakefulness when tired or sleepy.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): NoDoz, Stay Awake, Vivarin

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

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

  • anxiety
  • colitis
  • diabetes
  • heart disease or irregular heartbeat
  • high blood pressure
  • insomnia
  • kidney disease
  • liver disease
  • panic attacks
  • peptic ulcer disease
  • seizure
  • thyroid disease
  • an unusual or allergic reaction to caffeine, aminophylline, theophylline, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the label. You can take this medicine with or without food. If it upsets your stomach, take it with food. Take your medicine 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. This medicine is not approved for use in children under 12 years old.

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

This medicine may also interact with the following medications:

  • cimetidine
  • ketoconazole
  • ketoprofen
  • medicines for colds or breathing difficulties
  • phenobarbital
  • phenytoin
  • stimulant medicines for attention disorders, weight loss, or to stay awake
  • theophylline

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?

This medicine has about as much caffeine as a cup of coffee. Limit the use of caffeine-containing medications, foods, or drinks while taking this product. Too much caffeine may cause you to feel nervous, irritable, or to have a rapid heart beat or trouble sleeping.

This medicine is for occasional use only. It is not intended for use as a substitute for sleep. If fatigue or drowsiness continues, see a doctor. If you have been taking this medicine regularly, you can get withdrawal symptoms when you stop taking it. You may feel tired, dizzy, nervous, or have a headache.

Do not take this medicine close to when you want to sleep.

Talk to your doctor or health care professional before you take any other over-the-counter medicines, especially cold and allergy medicines.

Do not take this medicine with grapefruit juice; this may increase the effects of caffeine.

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
  • bloody, dark stools
  • breathing problems
  • confused, irritable
  • fast, irregular heartbeat
  • fever
  • infection
  • loss of appetite
  • seizure
  • trembling
  • trouble passing urine
  • trouble sleeping
  • unusual bleeding or bruising
  • vomiting

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

  • dry skin
  • frequent passing of urine

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.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Avoid storing at high temperatures. Protect from moisture. Throw away any unused medicine after the expiration date.

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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