i think larium, or something else that sounds similar to it, can make people hallucinate as a side effect.

whatever anti-malaria drug you end up taking, be sure to put on mosquito repellent lotion. i'm not sure if they're available in qatar though. use mosquito nets when sleeping too. i've heard that citronella and lemongrass act as natural mosquito repellents and there are organic sprays & lotions available from where i come from.