NSAIDS have antipyretic activity and can be used to treat fever.   Fever is caused by elevated levels of prostaglandin E2 , which alters the firing rate of neurons within the hypothalamus that control thermoregulation.   Antipyretics work by inhibiting the enzyme COX, which causes the general inhibition of prostanoid biosynthesis ( PGE2 ) within the hypothalamus .   PGE2 signals to the hypothalamus to increase the body's thermal set point.   Ibuprofen has been shown more effective as an antipyretic than paracetamol (acetaminophen).   Arachidonic acid is the precursor substrate for cyclooxygenase leading to the production of prostaglandins F, D & E.
NSAIDs may also interact with certain herbal preparations sold as dietary supplements. Among the herbs known to interact with NSAIDs are bearberry ( Arctostaphylos uva-ursi ), feverfew ( Tanacetum parthenium ), evening primrose ( Oenothera biennis ), and gossypol, a pigment obtained from cottonseed oil and used as a male contraceptive. In most cases, the herb increases the tendency of NSAIDs to irritate the digestive tract. It is just as important for doctors to know which herbal remedies the patient is taking on a regular basis as it is for doctors to know the other prescription medications which are being taken.
In the past several years, some newer medications have come on the market; these are commonly referred to as COX-2 inhibitors . Remember, all NSAIDs work against cyclooxygenase (COX). Traditional NSAIDs (. Ibuprofen, Motrin, Aleve) work against both COX-1 and COX-2. COX-1 and COX-2 are both types of cyclooxygenase enzymes that function in your body. The new medications (. Celebrex) work primarily against COX-2, and allow COX-1 to function normally. Because COX-1 is more important in producing the protective lining in your gut (gastric mucosa), these newer NSAIDs are believed to have less of a risk of causing stomach ulcers.