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.
Another possible cause of leg burning sensation is meralgia paresthetica, which is pain in the outer thigh due to compression of the lateral femoral cutaneous nerve, one of the main nerves within the thigh. Chronic conditions, such as multiple sclerosis, can also cause the sensation of burning in the legs.