Ketotifen is used to help prevent asthma attacks. It will not relieve an asthma attack that has already started.

Ketotifen must be taken continuously in order to be effective.

Continue taking your current asthma medications until instructed otherwise by your doctor.

Ketotifen may be taken with or without food.

Dosing

The dose of ketotifen will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of ketotifen. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage form (tablets and syrup):
  • For asthma:
    • Adults and children 3 years of age and older The usual dose is 1 milligram (mg) (1 tablet or 5 milliliters [mL] of syrup) twice daily, once in the morning and once in the evening.
    • Infants and children from 6 months to 3 years of age Dose is based on body weight and must be determined by the doctor. It is usually 0.25 mL (50 mcg or 0.05 mg) of syrup per kilogram (kg) (110 micrograms [mcg] or 0.110 mg per pound) of body weight twice daily, once in the morning and once in the evening.

Missed dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

To store this medicine:

• Keep out of the reach of children.
• Do not store tablets in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Ask your health care professional how you should dispose of any medicine you do not use. Be sure that any discarded medicine is out of the reach of children.

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For ketotifen, the following should be considered:

Allergies Tell your doctor if you have ever had any unusual or allergic reaction to ketotifen. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Diet Make certain your health care professional knows if you are on any special diet, such as a low-sugar diet. The syrup contains carbohydrates.

Pregnancy Ketotifen has not been studied in pregnant women. However, studies in animals have shown that ketotifen crosses the placenta and, at high doses, cause problems. Before using this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding It is not known whether ketotifen passes into human breast milk. However, it does pass into the milk of rats. It may be necessary for you to take another medicine or to stop breast-feeding during treatment. Be sure you have discussed the risks and benefits of the medicine with your doctor.

Children This medicine has been tested in children and, in effective doses, has not been shown to cause different side effects or problems than it does in adults.

Older adults Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of ketotifen in the elderly with use in other age groups.

Other medicines Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking ketotifen, it is especially important that your health care professional knows if you are taking any of the following:

• Antidiabetic agents, oral May increase the risk of bruising or bleeding and affect blood sugar concentrations

• Alcohol or
• Antihistamines or
• Hypnotics or
• Sedatives May increase the chance of side effects (i.e., drowsiness)

• Diabetes mellitus (sugar diabetes) May alter low-sugar diet (syrup contains carbohydrates)

• Epilepsy May increase risk of convulsions (seizures)