Would you consider prescribing NAC for a patient with OCD and a documented sulfa allergy?

I would consider using NAC if needed in a patient with a documented sulfa allergy because, although NAC is a sulfur-containing compound, it is chemically different from sulfonamides.

However, as with any new medical trial on a patient, individual hypersensitivity is a possibility. Provided there is a sulfa allergy, starting NAC at a smaller dosage may provide peace of mind, although there do not seem to be studies showing hypersensitivity reactions to NAC in sulfa-allergic patients. If you want to read more, below is the link to a newer article.

Smaga et al., PMID 33760228

Why would you use NAC at all in OCD, given the lack of positive results in the literature?