Should I be concerned about missong a dose of my anti-malaria medication?

December 15, 2006 7:59 AM

I just returned from an extensive road trip through Southern Africa including many malaria-prone areas. I took the anti-malaria medication Malarone once a day but missed a dose on the plane home. I received three mosquito bites in Mozambique (a malaria-prone country) the last day of the trip. Should I worry about contracting Malaria? Will the missed dose reduce the medication's effectiveness?

I'm trying not to freak out but I would really like to know whether there is legitimate reason for worry here. I'm particularly concerned about the missed dose as one is supposed to take the medication for a full seven days after returning home.

Also does anyone know how likely it is for a mosquito in a malria-prone area to be carrying malaria?

posted by yoel88 to Health & Fitness (9 answers total)

Speaking as someone who has had half a dozen coworkers come down with malaria in Gabon in the last few months, and not as a medical or drug expert, the drugs aren't 100% effective, so you need to keep an eye on yourself for a few months regardless of a skipped dose.
posted by cardboard at 8:32 AM on December 15, 2006

There is no reason to worry as long as you feel healthy. (I lived in Uganda for 2 years and only took anti-malarials for the first 5 months. I never contracted malaria at all, and I was medication-free.) Getting bitten by a mosquito does not guarrantee that you will get malaria.

That being said, as soon as you feel feverish, you need to assume that you have malaria. (Fever=Malaria for anyone who has been to a malarious region.) If you get a fever, make yourself an emergency appointment with a travel doctor. The doctor will prescribe you treatment, you will feel crappy for a day or two, and then you will get better.

Malaria makes you feel like crap, but is really only something to get overly worried about if you can't get treatment. (Which you can!)
posted by Kololo at 8:39 AM on December 15, 2006

Oh, and as far as how likely a mosquito is to be carrying malaria, it really depends on the precise location where you travelled. I lived in Kampala, the capital city, and the mosquitos mostly non-malarious; an hour outside of the city, in a more rural area, and the mosquitos were mostly malarious. So its really variable.
posted by Kololo at 8:42 AM on December 15, 2006

What cardboard said. When my husband and I went to Cambodia last year, we took the prophylactic (in this case, Lariam) dutifully and my husband got malaria anyway. Maybe I was just a bit more thorough in the mosquito repellent application, maybe he just drew the winning number in the lottery, who knows?

You need to watch yourself even if you hadn't missed a dose, so don't beat yourself up about that. But yeah, any sudden fever or chills, and get someone to take you to the ER right away. (Don't try to drive yourself!) They need to do the blood draw while you are having an episode, otherwise they may not be able to detect the parasite to make a diagnosis.
posted by ambrosia at 8:52 AM on December 15, 2006

Response by poster: Thanks guys. Malarone is supposed to be 98.3% effective which is a number I can live with. So I'm most concerned if missing a dose will lower the drug's effectiveness.

Also, for how long must I be on the lookout for sudden fever and chills? A month? A Year?
posted by yoel88 at 8:58 AM on December 15, 2006

It's my understanding that the little buggers can hang out in your liver for up to one year before making you ill, but I think that's the outside limit. In my husband's case, he got sick two months after we returned from Asia.

And I'm not sure where you are getting your 98.3% number from- there is effectiveness, but the malaria parasite develops resistance to drugs over time, including malarone, so the actual benefit is not always certain. This is one of the reasons why you have to keep an eye out after you leave a malaria zone.
posted by ambrosia at 9:06 AM on December 15, 2006

I was on a military field deployment to Kenya about 12 years ago for two months... got nailed by lots and lots of mosquitoes and probably missed a dose here or there. No malaria.
posted by rolypolyman at 9:42 AM on December 15, 2006

There's a lot of good basic info about malaria here.
posted by Steven C. Den Beste at 11:00 AM on December 15, 2006

And now that we got all that out of the way.... tell us about your trip!
posted by owenville at 2:38 PM on December 15, 2006