A single dose of sulfametopyrazine versus 7 days of ampicillin in acute on chronic bronchitis.

Forty-two patients with acute on chronic bronchitis received in double-blind fashion either a single dose of 2 g of sulfametopyrazine or ampicillin 250 mg thrice daily for 7 days. There were no significant differences between treatments in the number of patients achieving white sputum, the time to do so, or the incidence of pathogens at the end of treatment. Blood levels of sulfametopyrazine between 8 and 24 hours and on the seventh day were likely to result in sputum concentration adequate to kill Haemophilus influenzae.