What to Know About Mefloquine Side Effects in Veterans

Medically Reviewed by Poonam Sachdev on June 08, 2022
5 min read

Mefloquine is an anti-malarial drug that can have many different side effects. Some of these can be difficult to handle if you’re not prepared. 

Mefloquine was prescribed for a large number of military personnel prior to 2009. It’s still sometimes prescribed, but only for people who can’t take an alternative anti-malarial drug called doxycycline. 

Mefloquine's side effects for military personnel could be a consequence of taking the drug during your service. If you experience severe or lasting side effects from taking mefloquine, then you could qualify for disability compensation from the U.S. Department of Veterans Affairs (VA). 

Mefloquine is the generic name for an anti-malarial medication. It used to be produced under the brand name Lariam. The drug has a bitter taste. It’s only available by prescription in the U.S. 

Mefloquine was approved for use by the U.S. Food and Drug Administration (FDA) in 1989. Then, in 2013, the FDA published a safety alert about the drug and placed a black box warning on the drug label. This is the strongest warning that the FDA can place on a drug. The warning is due to newer data on the strong psychological side effects that are sometimes caused by taking mefloquine. 

Mefloquine is used for both the prevention and treatment of a disease called malaria. It’s one of three main drugs that are currently used to prevent malaria. The other two are doxycycline and atovaquone-proguanil (A/P). 

Malaria is common in Iraq, Afghanistan, and much of Africa, South America, and Southeast Asia. Mefloquine is no longer effective against malaria strains occurring in Southeast Asia, though, so you’ll need to use a different drug if you’re traveling there. 

Malaria is caused by a parasitic infection. The parasite is able to infect certain types of mosquitos. It then uses these insects to move into human hosts. You can die from malaria if it’s not treated. 

Your doctor will prescribe mefloquine when you’re traveling to a location where malaria is common. 

Mefloquine is usually safe for all ages. You can take it when you’re pregnant and breastfeeding. It was prescribed for many military service members who were deployed to Iraq and Afghanistan before 2009. 

These days, though, it’s only prescribed if you can’t take doxycycline. This could be for any number of reasons, including side effects and interference with other medications. You should talk to your doctor to determine which anti-malarial medication is right for you. 

One of the advantages of mefloquine is that you only need one pill every week. You begin taking the medication at least two weeks before you travel, the entire time that you’re in a malaria-heavy area, and for four weeks after leaving. 

Mefloquine can cause a number of concerning side effects. You shouldn’t take mefloquine if you have: 

Mefloquine can also interact with other medications that you might be taking. Your doctor will decide how to handle other medications if you need to take anti-malarial medication for travel. 

Like other anti-malarial medications, mefloquine can have a number of mild side effects. Mild side effects include: 

  • Dizziness
  • Trouble sleeping
  • Anxiety
  • Vivid dreams
  • Bad dreams

Mefloquine can cause additional mild side effects if you’re taking it on an empty stomach. These include: 

If your symptoms aren’t too troublesome, then you should continue to take mefloquine. Try taking it right after eating to relieve some of the mild symptoms. 

Unfortunately, the drug can also cause more severe symptoms. Severe mefloquine toxicity can lead to: 

These side effects can be much more problematic. They can even last for months or years after you’ve stopped taking the medication. 

Most side effects will show up within the first few weeks of taking mefloquine. You may want to start your prescription early so you have time to check for side effects before going on your trip. 

Talk to your doctor immediately if you begin to experience any severe side effects from taking this drug. 

Researchers have specifically looked for mefloquine side effects in military personnel. A number of studies only observed the effects of this drug in military service members, not the general public. 

One study looked at almost 20,000 veterans who were deployed between 2001 and 2008. Veterans within this population did have some problematic mental health side effects, but researchers found that most of these negative effects were more closely associated with the intensity of their deployment experiences, not their use of particular anti-malarial drugs. Still, keep in mind that this study wasn’t meant to intensively study all of the possible side effects of mefloquine.  

Another study compared about 36,000 military personnel who took mefloquine to approximately 318,000 who took doxycycline and about 13,000 who took A/P. This study found a significant increase in the amount of anxiety felt by actively deployed troops who were on mefloquine compared to doxycycline. They also found an increased risk of PTSD among non-deployed troops who were taking mefloquine compared to those taking A/P. 

Finally, people who had been diagnosed with psychological conditions showed increased odds of developing insomnia, adjustment disorders, and other psychological conditions on mefloquine compared to doxycycline. However, these results were not statistically significant. Many more studies are needed to fully understand the way that this drug impacts military personnel who have vastly different backgrounds and deployment experiences. 

The VA offers a variety of services to people who experience long-term side effects from the use of mefloquine. These services can include: 

  • Health care
  • Disability compensation
  • Health registry evaluations — free assessments that look for long term problems caused by environmental hazards, they’re available even if you don’t have VA health care
  • Survivor and dependent benefits — these apply if a military veteran dies from health concerns associated with their mefloquine side effects

You can file a claim with the VA for disability compensation if you believe that your health concerns are related to mefloquine use in the military. This can be done online, or you can consult your local VA office. They’ll decide your eligibility on a case-by-case basis. 

You may be eligible for military benefits if you served in the active military, navy, or air services. 

There’s a minimum duty requirement if you enlisted after September 7, 1980. In this case, you need to have served for at least 24 consecutive months or completed a full period of active duty to qualify. This minimum service doesn’t apply, though, if you were discharged because of a disability that was caused by — or made worse by — your service. It also doesn’t apply in cases of discharge for hardship. 

However, you likely won’t qualify if you received a dishonorable discharge. 

Whether or not you have other health care won’t affect the benefits that you can get from the VA. You should contact your local VA office to discuss your eligibility for services like VA health care and disability compensation.