Does Urinary Antiseptic Antispasmodic Interact with Antacids Containing Calcium?
Urinary Antiseptic Antispasmodic and Antacids Containing Calcium have a moderate drug interaction according to U.S. FDA drug labeling data. May reduce absorption of hyoscyamine and cause urine to become alkaline, reducing methenamine effectiveness. Space doses 1 hour apart. The mechanism involves reduced absorption and urine alkalinization. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Moderate
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Urinary Antiseptic Antispasmodic and Antacids Containing Calcium occurs because reduced absorption and urine alkalinization. Clinically, this means may reduce absorption of hyoscyamine and cause urine to become alkaline, reducing methenamine effectiveness. space doses 1 hour apart. This is classified as a moderate interaction. While it may not require stopping either medication, your healthcare provider should be aware you are taking both so they can monitor for potential effects and adjust treatment if necessary.
What To Tell Your Doctor or Pharmacist
If you are taking Urinary Antiseptic Antispasmodic and your doctor is considering prescribing Antacids Containing Calcium (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider