1 One drug, TGN1412, was tested on animals and in humans. 2  All the human patients suffered life-threatening side-effects which didn't appear in animals. 3  Not all drugs are used for the original purpose they were designed for. 4  Animal testing can't show all the potential uses of a drug.erhaps the law could be changed so that animal testing was optional, rather than compulsory. Scientists could decide not to test drugs on animals if they knew that it was safe to do so. We would need alternatives to animal testing, which could safely test drugs without harmful consequences for humans.
The feeling of itching urges one to scratch the site which causes more irritation and itching. Thus it goes as a cyclic reaction making one to itch more vigorously. Itchy legs can cause common symptoms like irritation of the skin in the legs, redness, pain and formation of red lesions on the legs. In severe case it may cause bleeding of skin due to repeated scratching. Itching can cause pain and discomfort feeling.
1 But sarcoidosis can also show up suddenly with the appearance of skin rashes.  Tender, raised, red bumps (called subcutaneous sarcoidosis or erythema nodosum) on the shins of the legs, or less frequently on the arms, are common and can cause leg or arm pain.