Thank you for your question. Accutane (isotretinoin) is a medication commonly used to treat severe acne, while Gardasil 9 is a vaccine that protects against the human papillomavirus (HPV). Generally, there are no known interactions between isotretinoin and the Gardasil 9 vaccine. Here are a few points to consider: Safety: It is generally considered safe to receive the Gardasil 9 vaccine while on Accutane. There are no studies or reports indicating that isotretinoin interferes with the efficacy or safety of the Gardasil 9 vaccine. Immune Response: Isotretinoin does not significantly affect the immune system, so it should not impair your body's ability to respond to the vaccine. Consult Your Physician: Even though there are no known interactions, it's always a good idea to consult your dermatologist or healthcare provider before receiving any vaccine while on medication. They can provide personalized advice based on your overall health and treatment plan. Feel free to discuss any concerns with your healthcare provider to ensure you are making the best decision for your health. Best regards,