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Malaria Pills and Birth Control

Travel Forums Central/South America & The Caribbean Malaria Pills and Birth Control

1. Posted by busysuzy (Budding Member 2 posts) 4y

I'll be travelling all over South America for nearly 5 months with my boyfriend. We will travel in Brazil, Uraguay, Argentina, Chile, Peru, Bolivia, Ecuador, and Columbia. After researching extensively about which malaria medication to take, I've decided on Larium (brandname Mefloquine) because it is recommended for long periods of time, and you only take it once a week.

Does anyone know if Larium will decrease the effectiveness of the birth control pill? There's not a lot of information about that specific drug interaction online, but it's VERY important that the birth control works effectively while I'm taking Larium. Surely there must be a lot of women travellers who are on birth control AND taking malaria pills??

Also, anyone know if alcohol interferes with Larium?

Any info would be great. Thanks!

2. Posted by Isadora (Travel Guru 13926 posts) 4y

Hi Suzy,

No, mefloquine (brand name is Larium) does not lower the effectiveness of birth control pills. In fact, it is recommended that women who are able to conceive, should take birth control pills for the duration of the Larium usage and continued for 3 months post Larium. It can cause serious defects to a fetus during the first trimester. Only women in their second and third trimesters can take it and only if entering an area where malaria is endemic. Even then it can cause problems for the baby. So, you are good to go with your OCs.

Of the 5 anti-malarial medications, doxycycline is the only one I'm aware of that lowers the OCs' effectiveness and then it's only for about 3 weeks. Though, for someone only traveling for that period of time, it's kinda tough as condoms would have to be used.

Keep in mind, Larium is well-known for it's side effects. These include dizziness, nightmares, muscle pain, hallucinations, headaches, diarrhea and a few more psychological problems. Larium is not recommended for scuba divers as it can interfere with your fine coordination and spacial acuity.

Hope that helps!

3. Posted by busysuzy (Budding Member 2 posts) 4y


Thank you so much for your prompt and informative reply! I feel much better about being on birth control while taking Larium. Yes, I'm very familiar with the infamous side effects of dizziness, and especially bad dreams and hallucinations. I was really concerned at first, but after giving it some thought, I decided that malaria must be pretty bad for people to subject themselves to medicines with these kind of side effects in order to avoid the disease. Besides, the US government gives it to Army and Peace Corp volunteers who are in high-risk areas for long periods of time. So I'm sure thousands of people have been on it before with few or no side effects.

You seem to have done your research on this; have you or someone you know taken Larium before? Where were you traveling? Were you (or the person you know) taking birth control at the time by any chance?

Anyone else have any experience taking Mefloquine/Larium before? Let me know!

4. Posted by Isadora (Travel Guru 13926 posts) 4y

Hi Suzy,

Well, you found out enough information about the side effects, which is a good thing.

My 'previous working life' (20+ years) was that in biomedical research and pharmacology. Though I have not taken mefloquine myself, I have taken chloroquine while in Panama. (Panama has not seen chloroquine-resistant malaria - yet.) But, I also have a broad base of resources, online and in person, to assist in my replies.

As for the Army, Navy and Peace Corp, they are slowly moving over to using Malarone. Though the two components that make up Malarone do have long-term histories and have been proven safe individually, the combination of the two and Malarone's side effects long term are still being monitored. Designed for the military and many industries are starting to require it. The perk there - the cost is covered and it's not cheap. The Peace Corp, from what I have gathered, is splitting the cost for those willing to take it. I may be wrong...

Personally, I'm used to taking medication every day, whether it be a prescription or just my vitamins. It's a routine I've become accustomed to over time. For me, doxycycline would be the drug of choice. I know condoms can be a real pain when you're not used to using them. (I haven't had to deal with that for 22 years. Hysterectomy at 36.) But, whether it's 1 or 2 pills taken daily for X amount of time, it works for me. I honestly had to mark a calendar to remember when our chloroquine needed to be taken as it's once a week too.

I've rattled on enough. Larium and your BCs will not be a problem. I can attest to several members who have experienced some of the more severe side effects and stopped taking the medication.

As a side note, doxycycline, though taken for 3-4 week (daily) after your return) has a history that it can be taken for (up to) 2 years non-stop. It's the same dosage as used to treat acne and will not interfere with other antibiotics you may need if injured or fall ill. Larium does not have that type of track record.

Okay, done talking!

5. Posted by KyleMac (Full Member 60 posts) 4y

lol what an awesome reply! You are the type of member that makes this website great. haha soooo good!!

6. Posted by Isadora (Travel Guru 13926 posts) 4y

Quoting KyleMac

lol what an awesome reply! You are the type of member that makes this website great. haha soooo good!!

Thanks Suzy and Kyle! I happy you both found the information of use.

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