Can I prevent HIV infection if I take drugs after unsafe sex?


The only way to ascertain HIV status is to take a test at least three months after exposure.

Photo credit: Fotosearch

What you need to know:

  • Anti-retroviral treatment should be taken as soon as possible after exposure.
  • Taking the medication for two weeks means it would be less effective.

Dr Flo,
If I am exposed to unsafe sex and I take post-exposure prophylaxis for only two weeks, can I protect myself from HIV?

Dear Bob,
Scientific research shows that for there to be higher chances of effective prevention of HIV, anti-retroviral treatment should be taken as soon as possible after exposure (within less than 72 hours) and the medication should be taken for at least four weeks. Taking the medication for two weeks means it would be less effective. The only way to ascertain HIV status is to take a test at least three months after exposure.

Dr Flo,
In a couple, is it possible for one person to be HIV positive and the other one negative? If yes, what is the science behind it?

Dear Val,
There are people who have repeated sexual intercourse with HIV positive partners while remaining negative. This is called HIV discordance, and the reason for this is not well understood. In rare circumstances, this is due to HIV resistance in the negative partner. However, with each sexual encounter, there is still a risk of contracting HIV. This risk increases if you have a sexually transmitted disease, or if your partner has a high viral load because they are not taking their medication properly. The risk decreases if your partner is taking anti-retroviral medication correctly, if you are using pre-exposure prophylaxis (medication to prevent HIV) or if you are using condoms correctly and consistently. It is not advisable to expose yourself knowingly and repeatedly, because if you get infected during one encounter, the HIV infection will remain for the rest of your life.

Dr Flo,
I am a 16-year-old Form Two student and I still wet the bed at different times at night. What can I do to avoid this embarrassment? We are reopening school and I need help.

Dear S B,
In many cases, the cause of bedwetting may not be known. Some may have an over active bladder or a problem with the nerves and muscles in the bladder. There are two kinds of treatment: behaviour therapy, and the use of medication. You need to take adequate amounts of water during the day, so that you are not thirsty in the evening. You should also make a habit of using the toilet regularly during the day, every two to three hours. Avoid taking large amounts of liquid after 6pm, and be sure to use the toilet just before going to bed. You can use an alarm to wake up once or twice during the night so that you can go to the toilet. The timing of the alarm should be adjusted to just before you wet the bed. It might take some time to get the timing right, and you have to be patient. Usually ,within three months, you should be able to stay dry most nights. You need to be reviewed by a doctor every few months until you stop bedwetting. If the above measures do not work, you can also be started on medication to help “strengthen” the bladder muscles. The most important thing for you is to believe that you can get dry, to maintain a positive attitude and to celebrate every victory.

Dr Flo,
What causes tonsil stones and how do I get rid of them?

Dear Vera,
Tonsil stones or tonsiloliths are white or grey balls that form on the surface of the tonsils and smell bad. The tonsils are lymphatic glands at the throat and they have an irregular surface. Bacteria, mucous, dead cells, and food particles can become trapped in the folds on the surface of the tonsils. The trapped substances then coalesce together and form the bad-smelling chunks. If these chunks harden, they are called tonsil stones or tonsiloliths. Tonsil stones are more common in people with chronic tonsillitis, or sinusitis and post-nasal drip.

These stones may cause bad breath, bad taste in the mouth, throat discomfort, difficulty swallowing or ear pain. Other than this discomfort, tonsil stones are usually not dangerous.
To manage them, observe good oral hygiene by brushing your teeth after meals, gargle using salt water or a mouth wash to reduce the bad breath, or have the stones removed by the doctor. Before brushing your teeth, remove food particles from your mouth by drinking water and by swishing water in your mouth and spitting out. It would be advisable to visit a dentist and ENT specialist so that any underlying problem can be treated.

Dr Flo,
How can I manage recurrent leukoplakia?

Dear Najib,
Leukoplakia means that you have thick white patches on the gum, inside of the cheeks and sometimes the tongue that cannot be scraped off. If the white patches can be scraped off, they are likely to be from a fungal infection that can be treated using antifungal oral drops or gel. There is no known cause of leukoplakia, but you are at a higher risk if you have had long term exposure to tobacco, if you have jagged or sharp teeth constantly scrapping your tongue, if you have ill-fitting dentures or if you have long term alcohol use. You may also get leukoplakia as a consequence of a viral infection (Epstein Barr Virus) if your immune system is weak for instance due to an HIV infection.

Leukoplakia is usually harmless and recurrent in most people. However, in a few people it can lead to oral cancer. The best way to manage it is to stop using tobacco and reduce on alcohol intake. If you have HIV infection, taking anti-retroviral drugs may help clear it. See a dentist for examination of the patches, and samples may be checked for cancer. If the lesions show early signs of cancer, they can be removed surgically or using laser or the cells destroyed by freezing.

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