The toxic effect is related linearly through a relatively large range of body weights, to the body weight of the victim, and, The mechanism of toxicity is the same for âsimilar animalsâ, i. e. one may conduct toxicity tests on say rats or mice and apply the LD50 data to human, since both are mammals.
For moderate menstrual cramps, the nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen [Advil, Motrin, Nuprin, etc.] or naproxen [Aleve, Anaprox, Naprosyn, Naprelan]) are often helpful.
In the latter category are several mild anti-inflammatory drugs (ibuprofen, naproxen), as well as acetaminophen. These are mainly meant for use with short-term, acute pain -- menstrual cramps, tension headaches, minor sprains -- what are known colloquially as everyday aches and pains..