Applies to zafirlukast: oral tablet.
Serious side effects of Zafirlukast
Along with its needed effects, zafirlukast may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur while taking zafirlukast:
Less common
- Cough or hoarseness
- fever or chills
- lower back or side pain
- pain
- painful or difficult urination
Rare
- Abdominal or stomach pain
- clay-colored stools
- dark urine
- diarrhea
- dizziness
- headache
- itching
- loss of appetite
- nausea
- rash
- unpleasant breath odor
- unusual tiredness or weakness
- vomiting of blood
- yellow eyes or skin
Incidence not known
- Attack, assault, or force
- attempts at killing oneself
- discouragement
- dry mouth
- fear or nervousness
- feeling sad or empty
- fever with or without chills
- general feeling of tiredness or weakness
- hyperventilation
- irregular heartbeats
- irritability
- lack of appetite
- large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
- loss of interest or pleasure
- restlessness
- seeing, hearing, or feeling things that are not there
- shakiness in the legs, arms, hands, or feet
- shortness of breath
- sleeplessness
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- tiredness
- trembling or shaking of the hands or feet
- trouble with concentrating
- trouble with sleeping
- unable to sleep
- unusual bleeding or bruising
Other side effects of Zafirlukast
Some side effects of zafirlukast may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.
Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
- Acid or sour stomach
- back pain
- belching
- difficulty with moving
- heartburn
- indigestion
- joint pain
- lack or loss of strength
- muscle aching or cramping
- muscle pains or stiffness
- stomach discomfort or upset
- swollen joints
- vomiting
Incidence not known
- Hives or welts
- redness of the skin
For Healthcare Professionals
Applies to zafirlukast: oral tablet.
General
The most commons adverse effects may be associated with headache or gastrointestinal disturbances. These symptoms are usually mild.[Ref]
Nervous system
Very common (10% or more): Headache (up to 12.9%)
Common (1% to 10%): Dizziness (1.6%)
Frequency not reported: Neuropathy, neuropsychiatric events[Ref]
Gastrointestinal
Common (1% to 10%): Nausea (up to 3.1%), diarrhea (up to 2.8%), abdominal pain (up to 2.8%), vomiting (up to 1.5%), dyspepsia (1.3%)[Ref]
Hepatic
In most of the postmarketing reports, the patient's symptoms abated and the liver enzymes returned to normal or near normal after stopping this drug.[Ref]
Common (1% to 10%): SGPT elevation (1.5%), AST (1.4%)
Rare (less than 0.1%): Hyperbilirubinemia without other elevated liver function tests; fulminant hepatitis or progressed to hepatic failure, liver transplantation and death
Postmarketing reports: Symptomatic hepatitis (with or without hyperbilirubinemia) without other attributable cause; hepatic dysfunction[Ref]
Musculoskeletal
Common (1% to 10%): Myalgia (1.6%), back pain (1.5%)
Frequency not reported: Arthralgia[Ref]
Other
Common (1% to 10%): Generalized pain (1.9%), asthenia (up to 1.8%), accidental injury (1.6%), fever (1.4%)
Rare (less than 0.1%): Increased theophylline levels with or without clinical signs or symptoms of theophylline toxicity when this drug was added to an existing theophylline regime.
Frequency not reported: Edema, malaise[Ref]
Respiratory
Common (1% to 10%): Respiratory tract infection (3.5%)[Ref]
Infections were usually mild or moderate, predominantly affecting the respiratory tract and not necessitating withdrawal from the therapy.
In clinical trials, an increased proportion of patients over the age of 55 years reported these infections. Infections occurred equally in both sexes and were associated with coadministration of inhaled corticosteroids.[Ref]
Cardiovascular
Rare (less than 0.1%): Bleeding disorders including menorrhagia, thrombocytopenia[Ref]
Dermatologic
Rare (less than 0.1%): Alopecia
Frequency not reported: Bruising, pruritus[Ref]
Hematologic
Rare (0.01% to 0.1%): Granulomatosis
Very rare (less than 0.01%): Agranulocytosis[Ref]
Immunologic
Systemic eosinophilia may also involve various body systems including vasculitic rash, worsening pulmonary symptoms, cardiac complications or neuropathy.[Ref]
Rare (less than 0.1%): Systemic eosinophilia, eosinophilic pneumonia, or clinical features of vasculitis consistent with Churg-Strauss syndrome[Ref]
Hypersensitivity
Frequency not reported: Urticaria, angioedema, rashes (with or without blistering)[Ref]
Psychiatric
Frequency not reported: Insomnia, depression[Ref]
