Malarone (atovaquone/proguanil) has an overall neuropsychiatric adverse reaction rate of ~0.05%. Looking specifically at nightmares, the rate is ~1.93%. On balance, it is one of the most effective, and safest, antimalarials on the market.
OTOH, the antimalarial mefloquine (e.g., Lariam) is notorious for neuropsychiatric side effects, including strange or vivid dreams, frank nightmares, delusions, anger episodes, psychosis, depression, mania, mood swings, panic attacks & suicidal ideation.
Here is an article from my "Ask RSD" column in a past issue of
Rodale's Scuba Diving magazine you might find informative.
"Lariam (mefloquine) is a very effective drug in preventing and treating malaria, but can give rise to unwanted side effects, including vivid and disquieting dreams, hallucinations, anxiety, depression, confusion and forgetfulness. The US package insert directs that "...caution should be exercised with regard to driving, piloting an airplane, and operating machinery as dizziness, a disturbed sense of balance, neurological or psychiatric reaction have been reported during and following the use of Lariam," and states that "dizziness, sensory & motor abnormalities, headache and fatigue have been recorded in patient's taking the drug." These cautions are consistent with suggestions by some in the medical and dive communities that mefloquine may produce side effects which mimic DCS. Interestingly, the German package insert adds it should not be used for "certain activities which have a need for full attention and undisturbed motor activity," with a specific direction that pilots should not use Lariam for the prevention of malaria during their work.
Of most concern to the diver are the positions of some medical professionals that the drug simply should not be taken for malaria prophylaxis by those who are actively diving. These sources include Rodale's Diving Doc," Dr. Samuel Shelanski, and the German Society for Tropical Diseases. This later group, whose policies can be used as a basis for professional and legal action in cases of harm resulting from a physician's failure to follow them, states that people with a special need for three-dimensional orientation, for example pilots, scuba divers and others, should not take mefloquine as prophylaxis. Similar advice regarding scuba diving is provided by Dr Bridget Farham, B.Sc (hons), Ph.D, MB.ChB., an expert on tropical medicines, and appears in the package insert accompanying mefloquine dispensed in South Africa.
The above information suggests it would be prudent to take this drug only after detailed discussion with a physician who is fully aware of its current status, and to closely monitor for any adverse reaction."
The FDA has come out with the following warning regarding mefloquine:
FDA Drug Safety Communication: FDA approves label changes for antimalarial drug mefloquine hydrochloride due to risk of serious psychiatric and nerve side effects .
Regards,
DocVikingo