It's only a partial answer, but a Nile crocodile can eat up to half its body weight at a sitting, according to National Geographic. Since few freshwater fish weigh half as much as a crocodile, we can probably assume these croc feasts occur when they're able to ambush ungulates (e.g. zebras and antelope).
Probably best to stick to the recommended dosing on the bottle though. For adults, that's 400-800mg four times a day (Maximum 3200mg/day US labelling or 2400mg/day Canadian labelling) Dosing for children is weight based. If your symptoms persist for more than 24 hours with ibuprofen, you should probably see your physician rather than keep taking the drug. Unless you are allergic to it, or have gastric issues such as ulcers or gastritis. Or have kidney disease, or advanced liver disease, or heart disease, or late in pregnancy.
Ibuprofen Dosage. Ibuprofen purchased over-the-counter comes in tablets or capsules of 200 mg, while prescription doses are available in 400, 600, and 800 mg tablets. For adults and children over 12 years of age, the usual dose of ibuprofen is one to two tablets or capsules every four to six hours as needed.Do not take more than 2,400 mg (12 capsules or tablets) of ibuprofen daily. Take ibuprofen with food or after meals if it seems to bother your stomach.buprofen (Advil, Motrin, and others) is a nonsteroidal anti-inflammatory drug (NSAID) used to relieve symptoms of arthritis, primary dysmenorrhea (pain during your period), fever, and pain and inflammation from other conditions. Low-dose ibuprofen (200 mg) is available over the counter.