Drug Interactions between bacampicillin and Effervescent Pain Relief

GENERALLY AVOID: Coadministration with antacids, H2-receptor antagonists, proton pump inhibitors, or other agents with acid neutralizing or reducing effects may decrease the oral bioavailability and plasma concentrations of ampicillin from bacampicillin. The exact mechanism of interaction is unknown but may be related to degradation of the prodrug when gastric pH is increased.

MANAGEMENT: The possibility of a reduced or subtherapeutic response to bacampicillin should be considered during coadministration with antacids, H2-receptor antagonists, proton pump inhibitors, or other agents that can increase gastric pH. Preferably, these agents should be avoided during therapy with bacampicillin, or an alternative antibiotic be prescribed if these medications cannot be discontinued. Patients treated with antacids (or oral medications that contain antacids such as didanosine buffered tablets or pediatric oral solution) may minimize the effects of the interaction with bacampicillin by separating the times of administration by at least 2 hours.

MONITOR: Agents that cause urinary alkalinization can reduce serum salicylate concentrations in patients receiving anti-inflammatory dosages of aspirin or other salicylates. The mechanism involves reduction in salicylate renal tubular reabsorption due to increased urinary pH, resulting in increased renal salicylate clearance especially above urine pH of 7. This interaction is sometimes exploited in the treatment of salicylate toxicity.

MANAGEMENT: Patients treated chronically with urinary alkalinizers and large doses of salicylates (i.e. 3 g/day or more) should be monitored for potentially diminished or inadequate analgesic and anti-inflammatory effects, and the salicylate dosage adjusted if necessary.