Assesses the efficacy of treatment with montelukast 10 mg PO QD x 5 days versus placebo for the treatment of viral-induced upper respiratory infection in healthy adults aged 18-50 years.

This is a randomized double-blinded placebo controlled trial to assess the efficacy of treatment with montelukast 10 mg PO QD x 5 days versus placebo for the treatment of viral-induced upper respiratory infection in healthy adults aged 18-50 years. All subjects complete daily assessments of cold symptoms, nasal clearance rates and secretion rates during each day of the study. Phlebotomy is performed once for the determination of cytokine genotyping and allergy skin testing is performed once for the assessment of atopy.

Inclusion Criteria:

• Adults 18 to 50 years of age.
• Male or female, who are not pregnant or lactating.
• Common cold symptoms for less than 24 hours.
• At least 2 of the following 9 symptoms: cough, headache, hoarseness, muscle ache, nasal drainage, nasal congestion, scratch throat, sneezing and malaise.

Exclusion Criteria:

• Investigational medication in past 30 days.
• Known hypersensitivity to any ingredients in study medication.
• History of asthma or other chronic diseases.
• Females of childbearing potential who are not using a medically acceptable form of birth control.
• Patients with nasal ulcers within the past 1 month, nasal surgery within the past 6 months, nasal trauma within the past 2 months or presence of nasal polyps or nasal deformities causing significant nasal obstruction.
• Females with a positive urinary HCG test.
• Patients with a positive rapid antigen test for streptococcal infection.
• Common cold symptoms for more than 24 hours.
• Patients who are users of illicit drugs.
• Patients who are on rifampin or phenobarbital.