Can Cosentyx (secukinumab) be taken with isoniazid?
Cosentyx (secukinumab) is an immunosuppressive biologic used for inflammatory conditions. Isoniazid is an antibiotic used to treat or prevent tuberculosis (TB). Whether they can be taken together depends on whether you are treating active TB versus latent TB and how your clinicians are monitoring you.
In general clinical practice, patients who need TB prevention or treatment (often latent TB) and who also need a biologic like Cosentyx are managed with coordination between prescribing specialists. The key issue is that anti-TNF safety guidance is more commonly spelled out in detail than for IL-17 blockers like secukinumab, so your prescribing clinician should confirm the plan.
What’s the main safety concern with combining them?
The concern is TB reactivation or inadequate TB control if immunosuppression is started without appropriate TB therapy. For that reason, clinicians typically do TB screening before starting biologics and then treat TB appropriately first, or start biologic therapy only under close supervision once TB treatment is in place.
What should you check with your doctor before starting or continuing Cosentyx?
Ask your clinician about:
- Whether your TB diagnosis is latent TB infection or active TB disease.
- Whether you have started (or are expected to start) isoniazid as preventive therapy or as treatment.
- When Cosentyx will be started relative to TB therapy.
- Whether you’ll need monitoring (symptom checks, labs, and possibly follow-up TB testing) while on both medications.
Are there known drug-drug interactions between Cosentyx and isoniazid?
Cosentyx is a monoclonal antibody and is not typically associated with the classic liver-enzyme interaction patterns seen with small-molecule drugs. The more practical overlap is safety monitoring, since isoniazid can affect the liver and biologics can affect immune response. Your prescriber should still review your liver function history and current medications.
What to do if you’re already on both
If you are already taking Cosentyx and isoniazid, do not stop either medication on your own. Contact the prescribing clinician promptly to confirm the plan for TB monitoring and liver safety (especially if you have symptoms like fatigue, nausea, abdominal pain, dark urine, or yellowing of the skin/eyes).
Sources
No usable labeled-interaction or official guidance links were provided in the materials here. If you share the country you’re in (e.g., US, EU, UK) and whether your TB is latent or active, I can tailor the answer more precisely to the typical prescribing guidance for that scenario.