Drug interactions
Isoniazid + Sodium picosulfate / magnesium oxide / anhydrous citric acid
Severity: Minor
Isoniazid and Sodium picosulfate / magnesium oxide / anhydrous citric acid: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Sodium picosulfate requires colonic bacteria to be converted into its active form, and antibacterial drugs may lessen bowel-cleansing efficacy. Isoniazid has antibacterial activity but mainly against mycobacteria, so the effect on colonic flora is uncertain and probably small.
What this interaction means in plain words
Isoniazid and Sodium picosulfate / magnesium oxide / anhydrous citric acid have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Possible reduced bacterial activation of picosulfate, although isoniazid's effect on colonic flora is not established.
What to do
No change is routinely needed. Confirm the quality of bowel preparation before colonoscopy and repeat or extend the preparation if inadequate.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Isoniazid and Sodium picosulfate / magnesium oxide / anhydrous citric acid, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Isoniazid
Frequently asked questions
Can I take Isoniazid with Sodium picosulfate / magnesium oxide / anhydrous citric acid?
MediHelp rates the interaction as minor. Isoniazid and Sodium picosulfate / magnesium oxide / anhydrous citric acid have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Sodium picosulfate requires colonic bacteria to be converted into its active form, and antibacterial drugs may lessen bowel-cleansing efficacy. Isoniazid has antibacterial activity but mainly against mycobacteria, so the effect on colonic flora is uncertain and probably small.
How serious is the interaction between Isoniazid and Sodium picosulfate / magnesium oxide / anhydrous citric acid?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No change is routinely needed. Confirm the quality of bowel preparation before colonoscopy and repeat or extend the preparation if inadequate.
What other medicines interact with Isoniazid?
MediHelp also lists interactions of Isoniazid with, for example, Bacillus calmette-guerin substrain tice, Benzhydrocodone / acetaminophen, Carbamazepine. The full list is on the Isoniazid page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
