COX-2 inhibitors block the action of an enzyme used throughout the body to make a large and diverse family of compounds called prostanoids that are involved in regulating myriad physiological actions, including inflammation, blood clotting and protection of the stomach lining from the destructive effects of digestive acids (Brown, 2004). Congress is questioning why the FDA didn't force Merck to study Vioxx's heart risk sooner. Merck is facing hundreds of lawsuits and potentially billions of dollars in damages from Vioxx. Pfizer, the makers of Celebrex, which is a rival of Vioxx, have not yet pulled the popular painkiller off the market, although Celebrex also increases cardiovascular diseases. Celebrex, approved by the Food and Drug Administration in 1998 for arthritis pain, has been prescribed to 27 million Americans and is the world's most widely prescribed arthritis drug ("Pfizer cites", 2005).
Zoloft, Prozac and Paxil, known as selective serotonin reuptake inhibitors or SSRIs, are antidepressants and act by enhancing the signals in nerves that transmit messages with serotonin, a neurotransmitter. , which are chemicals that are used to relay and modulate electrical signals between a neuron and another cell, are removed from the synaptic cleft by a process called reuptake. These drugs act on the neurotransmitter serotonin within the cell by delaying the reuptake process, thereby increasing the serotonergic effect. The regulators at the Food and Drug Administration ordered that all antidepressant drugs carry a prominent ‘black box’ warning to alert doctors that the medications increase the risk of suicidal thoughts and behavior among children and adolescents.