• worsening asthma symptoms;

• skin rash, bruising, severe tingling, numbness, pain, muscle weakness; or

• nausea, stomach pain, loss of appetite, itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

• headache;

• nausea, vomiting, diarrhea, stomach pain;

• weakness;

• dizziness;

• muscle pain; or

• fever, sore throat, cold symptoms.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.

What other drugs will affect zafirlukast?

Before using zafirlukast, tell your doctor if you are using any of the following drugs:

• aspirin;

• a blood thinner such as warfarin (Coumadin);

• tolbutamide (Orinase);

• erythromycin (E.E.S., E-Mycin, Ery-Tab, Erythrocin);

• theophylline (Elixophyllin, Respbid, Slo-Bid, TheoDur, and others);

• carbamazepine (Carbatrol, Tegretol); or

• phenytoin (Dilantin).

This list is not complete and there may be other drugs that can interact with zafirlukast. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Where can I get more information?

Your pharmacist can provide more information about zafirlukast.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.