What the FDA labels say about taking them together
Bacillus calmette-guerin substrain tice live antigen and isoniazid
Bacillus calmette-guerin substrain tice live antigen's FDA label of February 20, 2026 names isoniazid in its drug interactions section; the isoniazid label PlainMeds reads does not name bacillus calmette-guerin substrain tice live antigen. The bacillus calmette-guerin substrain tice live antigen label: “There are no data to suggest that the acute, local urinary tract toxicity common with BCG is due to mycobacterial infection, and antituberculosis drugs (e.g., isoniazid) should not be used to prevent or treat the local …”
Check it at the source: the bacillus calmette-guerin substrain tice live antigen FDA label on DailyMed (effective February 20, 2026); the isoniazid FDA label on DailyMed (effective July 8, 2025, OMNIVIUM PHARMACEUTICALS LLC.).
What does the bacillus calmette-guerin substrain tice live antigen label say about isoniazid?
Bacillus calmette-guerin substrain tice live antigen label, drug interactionsThere are no data to suggest that the acute, local urinary tract toxicity common with BCG is due to mycobacterial infection, and antituberculosis drugs (e.g., isoniazid) should not be used to prevent or treat the local, irritative toxicities of TICE BCG.
Bacillus calmette-guerin substrain tice live antigen label, warningsTICE BCG is sensitive to the most commonly used antituberculous agents (isoniazid, rifampin, and ethambutol).
Source: FDA drug label (TICE BCG), Merck Sharp & Dohme LLC, effective February 20, 2026 (SPL set c9b74876-e665-442b-87ad-b7333bc9a67a), via openFDA; the full label on DailyMed
What does the isoniazid label say about bacillus calmette-guerin substrain tice live antigen?
Isoniazid's label (effective July 8, 2025) does not name bacillus calmette-guerin substrain tice live antigen in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (isoniazid), OMNIVIUM PHARMACEUTICALS LLC., effective July 8, 2025 (SPL set 35400f1d-fd25-4bfa-a382-ac390e21bf2e), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Bacillus calmette-guerin substrain tice live antigen | Isoniazid | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $187.77 per vial Bcg (tice strain) vial | $3.40 per tablet 300 mg tablet |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once