Drug Interactions between Alka-Seltzer Lemon-Lime and peppermint oil

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.

ADJUST DOSING INTERVAL: Administration of enteric-coated, gastro-resistant formulations of peppermint oil (e.g., delayed or sustained release capsules) concurrently with antacids may cause premature dissolution of the enteric coating and early release of the peppermint oil, which could lead to gastrointestinal irritation and reduced therapeutic effects. The use of other medications that can reduce gastric acid, such as H2-receptor antagonists and proton pump inhibitors, may also cause similar issues.

MANAGEMENT: Acid-lowering medications should not be administered at the same time as enteric-coated, gastro-resistant formulations of peppermint oil. In general, H2-receptor antagonists and proton pump inhibitors should preferably be avoided, while antacids should be administered at least 2 hours before or 2 hours after the peppermint oil preparation. The labeling for the specific product should be consulted for administration recommendations and other guidance.