Is MDMA harmful

MDMA poisoning is rare if impossible as Downing notes that oral doses administered in therapy are less than 1 per cent of the LD50 (the dose that kills 50 per cent of rats or mice given the drug), implying a high margin of safety. What you need to watch out for is drinking too much water, or too little, or staying in a hot room. This could caused water toxicity (brain swelling = death) or you could get heatstroke/dehydrated leading to potential death. One pint an hour of water should suffice.

There is a debate re: neurotoxicity, but that isn't about death, neurotoxicity is unproven in human beings and in an American study they injected methamphetamine (a known neurotoxic drug) rather than MDMA when trying to prove MDMA is neurotoxic. Also, in later studies the amount are administered intraveneously, and x12 times the regular oral dose is injected. If you inject large amounts of any drug, it would probably be bad for you, even paracetemol which at that dose would kill you. So in my eyes, these studies prove little and seem poorly formulated.

I have read an article that stated that no one is allergic to MDMA (see Guardian Online) and in the British Science Journal is rated as safer than alcohol and tobacco by a big margin.

Too, it is worth pointing out that while in low non-regular usage it may be safe, using it many times probably isn't good for you, as binging on anything is bad for you! Once a month is probably safe to do - maybe 1/3 g of pure MDMA would be a safe amount depending on your size/weight. In my estimation, MDMA is a very safe drug and is used by many safely. Dont however mix it with MAOI's and SSRI prescription drugs - read the wiki page to find out what else you shouldn't mix it with.