Melia Azadirachta Oil Worst Irritant No known benefits Melia Azadirachta Oil description _Melia azadirachta_ oil (also known as neem oil) can be a skin irritant and is also poisonous if ingested. Avoid this form of neem and note that the constituents that make the oil a problem for skin aren’t present in the extracts, which is why the extracts are rated differently. Related ingredients: Neem Oil