Drug Interaction:
Warfarin, theophylline, aspirin,, Erythromycin, smoking Caution with drugs metabolized by CYP2C9 eg.tolbutamide, phenytoin, carbamazepine, or CYP3A4 eg, dihydropyrridine, cal channel blockers, cyclosporine, cisapride
Indication:
Prophylaxis and treatment of asthma
New Drugs Approved by (DCI) Drug Controller GENERAL - India For Marketing
(Ref- IDMA Publication)
Name of Drug Indication Date of Approval
Zafirlukast Anti-Asthmatic 03-12-2001
Patent Expiry Date of drugs (Ref - IDMA Publication)
Chemical Category Manufacturer/ US Patent
Ingredient- Marketer Expiration Date
Zafirlukast Respiratoty AstraZeneca 26-09-2010
Adverse Reaction:
Headache, g-i upset, rash, priritus, Malaise, increased serum transaminases, Discontinue tgherapy immediately following signs or symptoms of liver dysfunction
Respiratory infections in elderly Insomnia , irritability, restlessness,
Depression, suicidal thinking and behavoiur, Hallucinations, coinsider discontinuing therapy Rarely ,hepatitis, bruising bleeding, myalgia, Patients should be asked to report nausea,
Fatigue,loss of appetite, flu-like symptoms, Pain on right side of abdomen, Yellow coloration of the eyes Dark urine to doctor urgently
Contra-Indications:
hepatic impairment , cirrhosis, hypersensitivity, lactation.
Special precautions
Do not substitute for steroid therapy or use for acute attacks Moderate to severe renal impairment
Elderly, pregnancy
Discontinue if eosinophilic condition or a Chrug -Strauss syndrome develops
If signs or symptoms of hepatic impairment, measure transaminase and consider withdrawing therapy
Dosages/ Overdosage Etc:
Prophylaxis and treatment of asthma
Dosage-
1 tab twice daily between meals children - not recommended
Pharmacology/ Pharmacokinetics:
Ref- Drug Facts And Comparisons (2010)
Leukotriene Receptor Antagonists include-
Zafirlukast, Montelukast
Refer- Zafirlukast
Pharmacology-
Zafirlukast is a selective and competitive receptor antagonist of leukotriene D4 and E4
(LTD)4, and LTF4) components of slow reacting substance of anaphylaxis (SRSA) .
Cysteinyl leukotriene production and receptor occupation have been correlated with
the pathophysiology of asthma, including airway edema , smooth muscle constriction
and altered cellular activity associated with the inflammatory process hich contribute
to the signs and symptoms of asthma
Pharmacokinetics-
Zafirlukast is rapidly absorbed following oral administration . Peak plasma concentration
are generally acheived 3 hours after oral adminstration. The absolute bioavailablity of
zafirlukast is unknown. In 2 separate studies, 1 using a high fat meal and a high protein
meal, administration of zafirlukast with food reduced the mean bioavailbility by
approximetely 40%
Mean (% Coefficient of Variation ) Pharmacokinetic Parameters of
Zafirlikast Following Single 20mg oral Dose Administration to
Male Volunteers (n= 36)
Cmax Tmax AUC t 1/2 CL/f
(ng/mL) (h) (ng*n/mL) (h) (L/h)
326(31) 2(0.5- 5) 1137(34) 13.3(75.6) 19.4(32)
Zafirlukast Pharmacokinetic Parameters in Children
Mean (% coefficient of variation)
Children Children
Parameter 5 to 6 years of age 7 to 11 years of age
Cmax 756 (39%) 601 (45%)
(ng/mL)
AUC 2458 (34%) 2027 (38%)
(ng*h/mL)
Tmax 2.1(61%) 2.5(55%)
(h)
CL/f 9.2% (37%) 11.4 (42%)
(L/h)
Pregnancy and lactation:
Use contraindicated. Observe caution
Manufacturer Details