Phenylbutazone

Toxicity

Oral, LD50 = 238 mg/kg (mouse); Oral, LD50 = 781 mg/kg (rabbit); Oral, LD50 = 245 mg/kg (rat); Oral, LD50 = 375 mg/kg (rat)

The Uses of Phenylbutazone

Phenylbutazone, a nonsteroidal anti-inflammatory drug, is an efficient reducing cofactor for the peroxidase activity of COX. Phenylbutazone-dependent inactivation of COX and prostacyclin synthase is markedly increased in the presence of 100 μM hydrogen peroxide with half-maximal effects at Phenylbutazone concentrations of 100 and 25 μM for COX and prostacyclin synthase, respectively.

Indications

For the treatment of backache and ankylosing spondylitis

Background

A drug that has anti-inflammatory, antipyretic, and analgesic activities. It is especially effective in the treatment of ankylosing spondylitis. It also is useful in rheumatoid arthritis and Reiter's syndrome (investigational indication). Although phenylbutazone is effective in gouty arthritis, risk/benefit considerations indicate that this drug should not be employed for this disease. (From AMA Drug Evaluations Annual, 1994, p1822)

What are the applications of Application

Phenylbutazone is an inhibitor of Cox

Pharmacokinetics

Phenylbutazone is a synthetic, pyrazolone derivative. It is a nonhormonal anti-inflammatory, antipyretic compound useful in the management of inflammatory conditions. The apparent analgesic effect is probably related mainly to the compound's anti-inflammatory properties and arise from its ability to reduce production of prostaglandin H and prostacyclin. Prostaglandins act on a variety of cells such as vascular smooth muscle cells causing constriction or dilation, on platelets causing aggregation or disaggregation and on spinal neurons causing pain. Prostacylcin causes vascular constriction platelet disaggregation

Metabolism

Not Available