How can I get rid of this ammonia smell that remains on my underwear and not on my vulva or vagina?

To get rid of the ammonia smell on your underwear, you can try soaking them in a mixture of vinegar and water or washing them with baking soda. Additionally, make sure to thoroughly rinse your underwear after washing to remove any lingering odors. It may also be helpful to wear breathable cotton underwear to prevent odors in the future. If the odor persists, it is recommended to seek advice from a pharmacist for personalized guidance.