Can Cosentyx (secukinumab) cause weight loss?
Cosentyx is not known as a typical cause of weight loss. Commonly reported effects are related to infections and injection-site reactions, plus some lab changes, but weight loss is not a standard, well-established side effect in the usual prescribing information context.
If someone taking Cosentyx loses weight, clinicians generally look for other explanations first, such as:
- the underlying inflammatory condition improving or changing activity level
- reduced appetite or gastrointestinal illness (including infection)
- other medications that started around the same time
- thyroid issues, diabetes changes, or other unrelated medical causes
What side effects are more common with Cosentyx that could affect appetite or weight?
Cosentyx can increase the risk of infections. If an infection occurs, it may lead to reduced appetite, nausea, or general illness, which can indirectly contribute to weight loss. In addition, people sometimes report injection-site reactions or other nonspecific symptoms that can affect how they feel day to day.
When should weight loss be treated as a potential warning sign?
Contact a clinician promptly if weight loss is:
- unintentional and continuing
- paired with fever, persistent diarrhea, blood in stool, severe fatigue, or other signs of infection
- significant over a short period
- associated with trouble swallowing, ongoing vomiting, or severe abdominal pain
These combinations merit medical review because they could reflect an infection or another condition that needs treatment rather than being attributed to Cosentyx alone.
Could weight loss be from something else while on Cosentyx?
Yes. Weight changes often track with factors like:
- changes in psoriatic arthritis or psoriasis severity and activity level
- lifestyle changes after starting biologic therapy
- new or adjusted meds (for example, steroids, diabetes drugs, or appetite-affecting medications)
- comorbid conditions (thyroid disease, GI disease, malignancy, depression)
What should you do if you’re experiencing weight loss on Cosentyx?
It’s reasonable to report the weight change to the prescriber, including:
- how much weight you lost and over what time
- whether appetite, stomach symptoms, or fevers have changed
- when you started Cosentyx and any other new medications
A clinician can decide whether it’s likely related to Cosentyx versus another cause and whether you need testing (for example, infection workup or routine labs).
Sources: none provided in the prompt.