Antihistamine–decongestant combinations in adults
Two studies compared antihistamine–decongestant combinations with placebo. Dexbrompheniramine (a sedating antihistamine)–pseudoephedrine (6 mg/120 mg twice daily for 1 week) was significantly more effective than placebo for severity of cough. Adverse effects increased, including dizziness and dry mouth. In the other study, loratadine (a nonsedating antihistamine) pseudoephedrine (5 mg/120 mg twice daily for 4 days) did not show any difference between the study groups. Thirty percent of the intervention reported dry mouth,headache and insomnia compared with 21% in theplacebo group. This translated to an NNTH of 11.