Which herbal supplement is sometimes used for immune support but can interact with immunosuppressants?

• A. Garlic
• B. Echinacea
• C. Ginseng
• D. St. John's wort

Answer: (B)

Echinacea is used to support the immune system, but it can stimulate immune activity. Immunosuppressant medications are designed to dampen the immune response, so taking an herb that boosts immunity can counteract that effect or cause unpredictable immune reactions. This interaction is why echinacea is the best fit for a question about an immune-supportive herb that can interact with immunosuppressants.

Other options have different primary concerns that don’t align as closely with the scenario. Garlic and ginseng are more commonly noted for metabolic or cardiovascular interactions, while St. John’s wort is well known for broad drug interactions via enzyme induction but isn’t typically used for immune support. If you’re on immunosuppressants, it’s best to avoid echinacea unless a clinician clears it.