Do you avoid potassium citrate in patients with recurrent nephrolithiasis and hypocitraturia if they also take antihistamine medications?  

I know of no data showing effects of antihistamine meds on urine citrate or on the effects of potassium citrate on urine citrate. I made a Perplexity search which also found no evidence - this is not a topic I have personally researched because I have never encountered clinical issues about it. So -...