Inclusion criteria:
18 to 45 years old
Sex: Males and/or non-pregnant, non-lactating females
BMI: 18.5 to 24.9 weight in kg/(height in meter)
Able to communicate effectively with study personnel and willingness to follow the protocol requirements as evidenced by written informed consent
A physical examination with no clinically significant finding and laboratory normal tests
Do not take any chronic or acute medication for at least 1 week before the start of the study
No history of diseases affecting the pharmacokinetic processes of the drug
Exclusion criteria:
History of allergic responses to Montelukast or other related drugs, or any of its formulation ingredients
Have significant diseases (which might compromise the haemopoeitic, gastrointestinal, renal, hepatic, cardiovascular, respiratory, central nervous system, diabetes, psychosis or any other body system) or clinically significant abnormal findings during screening
History or presence of bronchial asthma
Smokers who smoke 10 or more cigarettes per day or 20 or more biddies per day or those who cannot refrain from smoking during the study period
History or evidence of drug dependence or of alcoholism or of moderate alcohol use
History of difficulty with donating blood or difficulty in accessibility of veins
Volunteers who have received a known investigational drug within five elimination half life of the administered drug prior to the initial dose of study drug or who have participated in a clinical drug study or bioequivalence study within 90 days prior to the initial dose of study drug, whichever is greater
Found positive in urine test for drugs of abuse done before check-in of period
History of difficulty in swallowing, or of any gastrointestinal disease which could affect drug absorption