The good news for you is large doses of generic Claritin are far superior to 1970s huge doses of diphenhydramine. Ragweed and tree pollen and mowing the lawn hammered me for many years. I will bet you can get a lot of generic Claritin for not much cash in Thailand. I now being 56 have outgrown virtually all my allergic responses and allergens. Good luck and hope their is an allergist somewhere in Cambodia who can set you up with a regimen of allergy shots. SCRATCH THE FOREGOING SENTENCES FROM YOUR MIND….JEEPERS, just reread the post. Hang tough, kiddo. Maybe it is some agent, allergen unique to the current environs. Maybe it will be absent in your new environs.