A lice-killing lotion containing 1% permethrin or a mousse containing pyrethrins and piperonyl butoxide can be used to treat pubic (crab) lice. These products are available over-the-counter without a prescription at a local drug store or pharmacy. These medications are safe and effective when used exactly according to the instructions in the package or on the label. Lindane shampoo is a prescription medication that can kill lice and lice eggs.
Trichomoniasis is another type of vaginal infection. It is caused by a single-celled parasite that is usually spread through sex. In addition to causing bleeding after sex, it can also cause vaginal discharge and itching.
If you have this problem, you should ask your partner to ejaculate outside or use a condom. However, many women also have a bad reaction to the latex and chemicals on condoms as well. If the odor primarily comes after sex, then simply wash the vagina with warm water and mild soap afterwards.