Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Accolate (Zafirlukast). If you are concerned about side effects, discuss the risks and benefits of Accolate (Zafirlukast) with your doctor.

The following side effects have been reported by at least 1% of people taking Accolate (Zafirlukast). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• abdominal pain
• Diarrhea
• headache
• muscle aches
• nausea
• rash
• trouble sleeping
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• general feeling of being unwell
• increased frequency of infections (e.g., lack of energy, Fever or chills, difficulty breathing, cough)
• itching
• joint pain
• signs of bleeding (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• flu-like illness, rash, pins and needles or numbness of arms or legs, and severe Sinusitis
• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Accolate (Zafirlukast).

Each white-to-off-white, round, biconvex, film-coated tablet, with surface markings, contains Accolate (Zafirlukast) 20 mg. Nonmedicinal ingredients: croscarmellose sodium, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, povidone, and titanium dioxide.

Do not take Accolate (Zafirlukast) if you:

• are allergic to Accolate (Zafirlukast) or any ingredients of the medication
• have reduced liver function

There may be an interaction between Accolate (Zafirlukast) and any of the following:

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Accolate (Zafirlukast). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take Accolate (Zafirlukast).

Asthma attacks: Accolate (Zafirlukast) should not be used to try to relieve acute asthma attacks. Have your rescue medication ready in case of an acute attack. Do not stop taking Accolate (Zafirlukast) without consulting your doctor.

Liver problems: Accolate (Zafirlukast) is not recommended for people with reduced liver function. It may also cause severe liver problems. If you develop jaundice (signs include yellowing of the skin or eyes); flu-like symptoms; nausea; fatigue; loss of appetite; itching; and pain on the right side of your abdomen, under the ribcage, stop taking Accolate (Zafirlukast) and contact your doctor immediately.

Warfarin interaction: Taking warfarin together with Accolate (Zafirlukast) significantly increases the time it takes blood to clot. People taking warfarin and Accolate (Zafirlukast) should have their bleeding times monitored closely and have their anticoagulant dose (warfarin) adjusted accordingly.

Pregnancy: Accolate (Zafirlukast) should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Accolate (Zafirlukast), contact your doctor immediately.

Breast-feeding: Accolate (Zafirlukast) passes into breast milk. If you are a breast-feeding mother and are taking Accolate (Zafirlukast), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The effectiveness and safety of Accolate (Zafirlukast) for children under 12 years of age have not been established.