How would I rid my underwear of the smell of buprenorphine/soldadine?

I have a prescription to buprenorphine. When I take my urine tests at the doctor, they tell me that when I take it, I get buprenorphine in my vagina. (I have a lot of weight on my pelvis). I have basically drenched my underwear in my urine. I have tried washing them twice, but I can still smell it. I honestly would prefer that my underwear didn’t smell like urine. Are there are any tips you have for getting my underwear clean of that urine?