Can Cosentyx (secukinumab) trigger cold sores or make them worse?
Cosentyx is an immunosuppressive medicine used for conditions like psoriasis and psoriatic arthritis. Because it affects immune responses, it can increase the risk of infections, including viral infections. Cold sores (herpes simplex virus, HSV-1) are viral infections, so Cosentyx could potentially allow a dormant cold sore virus to flare or increase the chance of getting one.
The most direct way to answer depends on your specific situation (prior history of cold sores, how you’re taking Cosentyx, and whether you’ve had herpes before), but the key point is that viral infections are a known concern with medicines like Cosentyx.
What symptoms would count as a cold sore?
Cold sores usually cause:
- Tingling, burning, or itching on the lip area
- Small fluid-filled blisters
- Crusting and healing over days
If you develop new sores around the mouth after starting Cosentyx, it can fit a cold sore pattern.
What should you do if you get a cold sore while on Cosentyx?
If you get mouth sores that look like cold sores:
- Contact your prescriber promptly, especially if it’s your first episode or it’s severe.
- Ask whether you should start an antiviral medication (commonly acyclovir/valacyclovir), since treatment works best when started early.
- Do not share lip balm/utensils while lesions are active, since HSV can spread by contact.
Your clinician may also advise whether to continue Cosentyx, hold a dose, or switch treatment based on severity and your infection history.
Does Cosentyx cause herpes in everyone?
No. Many people taking biologics like Cosentyx do not get herpes infections. Risk is higher in people with:
- A history of recurrent cold sores
- Frequent outbreaks without antivirals
- Situations that already stress or weaken immune defenses
When to seek urgent care
Get urgent medical help if you have any of the following:
- Eye involvement (red eye, eye pain, vision changes)
- Fever, rapidly spreading skin symptoms, or feeling very unwell
- A painful rash that’s not clearly a typical cold sore pattern
Other herpes-related concerns people ask about
People taking immune-modulating drugs sometimes worry about shingles (herpes zoster) as well. If you have a history of either cold sores or shingles, tell your clinician before starting or continuing Cosentyx so they can personalize risk and prevention.
If you tell me your dose schedule (monthly vs every 2 weeks), what condition you take Cosentyx for, and whether you’ve had cold sores before, I can help you think through your likely risk and what to ask your prescriber.