Hello,
Thank you for asking your query at DoctorSpring.
Sorry for my delay in the reply.
I understand your concern and I will try my best to help you. As you might know Crohn’s diseases is a need a long term treatment approach. Intermittent symptoms flare up can occur which can be well managed with drugs.

The approach to Crohn’s disease is complex and not limited to Mesalamine. “ There are two approaches to treatment - step-up therapy and top-down therapy. Step-up therapy typically starts with medications that are less potent and (often) associated with fewer side effects. If those therapies are ineffective, more potent (and potentially more toxic) medications are used. Top-down therapy starts with more potent therapies, such as biologic therapy or immunomodulator therapy, relatively early in the course of the disease before patients become glucocorticoid dependent, and possibly even before they receive glucocorticoids.”
Apart from Meselamine, you will need antibiotics (Metronidazole / Cipo) for this episode with or without glucocorticoids. Since you have significant perianal disease, this will require additional approach. (Antibiotic firsts, if no response Biological agents /immunomodulatory drugs)

Bottom line is your symptoms and flare ups can be controlled, but require a bit more aggressive treatment approach. I recommend a Gastroenetrolgist consultation with long term followup/
Hope this helps
Please feel free to ask follwoup questions
Thank you