trichomoniasis and metronidazole allergy?

[fromtheseaRN, BSN, RN]

i am a nursing student and i volunteer at a health clinic. last week we had a pt who had previously been treated for bacterial vaginosis with clindamycin 300mg bid x7 days. she came back and the infection had not cleared. the NP wanted to prescribe tinidazole to knock out the infection, and because she suspected it was actually trichomoniasis. unfortunately, this pt had hx of allergy to metronidazole (pustules on entire body). we searched every possible source to find an alternative treatment for her, to no avail. all that was recommended was the tinidazole or clindamycin. so, the pt was sent with a 2g 1 dose rx for tinidazole, to take 1 hour after taking 50mg benadryl, followed by 25mg benadryl q4h (not to exceed 400mg/24h).

i felt terrible that a pt was going home to take something she was allergic to. has anyone else encountered trich with an -azole allergy, and if so, what was your solution?

thanks!

[TakeOne]

I've encountered many cross-sensitivities and prescribing the most effective med with in conjunction with antihistamines and instructions to get to an ER pronto if reaction gets worse is not uncommon. I'm wondering, though, if a specimen of the discharge had been taken before treatment was initiated or before the antiprotozoal was ordered.

[fromtheseaRN, BSN, RN]

a specimen was taken and sent to a lab, i haven't been back since then so i'm not sure what the results were. the NP went ahead and ordered the tinidazole in the meantime based on the infection not clearing with antibiotics after the first time she was seen, and the discharge was yellow-green.

[LaurenMarie]

tell them to do an ABS to find out what bacteria it actually is... it will take a little while, but its better to know and then prescribe than to guess and prescribe something that *might* work.

[Elvish, BSN, DNP, RN, NP]

Not exactly the same situation, but when I was in nursing school I had a peds pt who had a vancomycin allergy (urticaria, pruritis). She had sepsis from her central line and since pulling the line wasn't an option at that point, and the bug was resistant to everything but vanc, they really didn't have a choice. She got premeded with Benadryl 30min before the antibiotic. Sure wasn't ideal but it worked.

[LaurenMarie]

That sounds really interesting! Amazing how medicine works sometimes!

[fromtheseaRN, BSN, RN]

tell them to do an ABS to find out what bacteria it actually is... it will take a little while, but its better to know and then prescribe than to guess and prescribe something that *might* work.

the only test i know called ABS is to test for syphillis, is this a different one? trich is diagnosed by viewing the protozoa under microscope, something that this free clinic doesn't have readily on hand :)

pt did have the classic symptoms of trich, plus metronidazole is effective against trich in addition to being used for bacterial vaginosis, so that's why the NP felt confident in prescribing it.

[EmOgle27]

At our office, we use Tindamax 500mg BID x 5 days when Metro-gel doesn't do the trick (hehe trich) or there is an issue.

[fromtheseaRN, BSN, RN]

At our office, we use Tindamax 500mg BID x 5 days when Metro-gel doesn't do the trick (hehe trich) or there is an issue.

hahahhaha! very punny!

tindamax is tinidazole, so we were trying to get away from that because of her -azole allergies.

[LaurenMarie]

Try Clindamycin for the patient...its pretty tolarable...

[LaurenMarie]

You can do an ABS for any bacteria you can get a sample of, which requires a gram stain... but I think trich is a parasite...

[fromtheseaRN, BSN, RN]

You can do an ABS for any bacteria you can get a sample of, which requires a gram stain... but I think trich is a parasite...

i think it's just a difference in terminology, we call it C&S here (culture and sensitivity). ABS here is a blood serum test that looks for syphilis antibodies (technically FTA-ABS).

trich is a protozoa, and the pt's first tx was clindamycin, which was ineffective.