IUD and mefenamic acid

October 27, 2018 6:10 PM

I got my first IUD this week (hormonal, not copper) and took mefenamic acid for the first day to ease the cramps. At the end of the day I noticed the box says: 'Unless your doctor or pharmacist has told you, do not use this product if you [...] are using an intrauterine contraceptive device'. Does anyone know why?

I have tried googling 'iud and mefenamic acid' but the only results are studies about the effectiveness of mefenamic acid to treat dysmenorrhea in patients with IUDs and articles about treating cramping after IUD insertion.

posted by aussie_powerlifter to Health & Fitness (5 answers total)

I'm not a gyn specialist, but I don't actually find any contraindications when looking at mefenamic acid in either US or UK databases. I skimmed what are likely some of the same studies you found and didn't immediately see anything regarding expulsion. I wonder if that manufacturer puts that warning (due to potential for increased bleeding) on all NSAIDs they produce.
posted by cobaltnine at 6:32 PM on October 27, 2018

IANYD, can't think of any reason it would be interacting, but it might be a social engineering thing to make sure people check in with their doctor if they're having ongoing cramping or pain after IUD insertion and check there's been no complication.
posted by chiquitita at 10:14 PM on October 27, 2018

It's either the psychological effect they are going for or it's that, if you were to have a perforation, the mild blood thinning effect that is common to NSAIDs in general could cause complications. At least that's my best guess...
posted by wierdo at 3:12 AM on October 28, 2018

Mefenamic acid is an NSAID that may reduce symptoms of dysmenorrhea. Uterine perforation by IUD might be mistaken for dysmenorrhea and a patient might take mefenamic acid not realizing that the pain is a sign of uterine perforation from their IUD.
posted by metasunday at 5:14 PM on October 29, 2018

Thanks everyone! I stopped at the pharmacy yesterday to ask about it and the pharmacist said it should be fine (the only contraindications she mentioned were a history of ovarian cysts or pelvic inflammatory disease), so I'd guess the answer is one of those suggested here or some combination.
posted by aussie_powerlifter at 12:45 AM on October 30, 2018