Acetaminophen causative agents

In addition to their beneficial effects, some medications may actually cause cellular injury and disease. An example of this phenomenon involves nonsteroidal anti-inflammatory drugs (NSAIDS). These drugs include aspirin (a derivative of salicylic acid), ibuprofen (arylpropionic acid, Advil ), and acetaminophen (para-aminophenol derivative, Tylenol ). Because of their beneficial pharmacological effects, consumption of these agents has increased significantly in recent years. NSAIDS have the ability to treat fever, pain, acute inflammation, and chronic inflammatory diseases such as arthritis. They are also used prophylactically to prevent heart disease, stroke, and colon cancer. 

Use in moderate pain Weak analgesic most effective when used with NSAIDs, aspirin, or acetaminophen This drug is not recommended in the elderly Will cause carbamazepine levels to increase 100 mg of napsylate salt = 65 mg of HCI salt Third-line agent for moderate-to-severe pain... 

Hemolytic anemia can be caused by eating foods (such as fava beans) or taking drugs (such as anti-malarial agents or acetaminophen) that have oxidizing properties. 

Hepatic necrosis can be classified by the zone of the liver tissue affected. Xenobiotics, such as acetaminophen or chloroform, that undergo bioactivation to toxic intermediates cause necrosis of the cells surrounding the central veins (centrilobular) because the components of the cytochrome P450 system are found in those cells in abundance. At higher doses or in the presence of agents that increase the synthesis of cytochrome P450 (inducers), the area of necrosis may incorporate the... 

There are two major classes of pain medications, nonopioids and opioids. The nonopioids used to treat mild pain include agents such as acetaminophen, both steroid and nonsteroidal antiinflammatory drugs (NSAIDs), and acetylsalicylic acid. Anticonvulsants suppress neuronal firing and are also helpful in neuropathic pain. Antiinflammatory agents (e.g., NSAIDs or corticosteroids) may be particularly helpful when bony involvement occurs and are often used for low-intensity pain. Steroids decrease inflammatory edema and are useful in cases of nerve and spinal cord compression, lymphedema, visceral pain caused by organ enlargement, and bone pain. Finally, short-term corticosteroid therapy may also produce euphoria (thus ameliorating less severe depressions) as well as reverse anorexia. 

Bioactivation is a classic toxicity mechanism where the functional group or the chemical structure of the drug molecule is altered by enzymatic reactions. For example, the enzymatic breakdown of the analgesic acetaminophen (paracetamol), where the aromatic nature and the hydroxyl functionality in paracetamol are lost, yields A -acetyl-p-benzoquinone imine, a hepatotoxic agent. Paracetamol can cause liver damage and even liver failure, especially when combined with alcohol. 

Much is known about the biochemical toxicology of hepatotoxicants, yet much remains to be learned. Hepatotoxicity resulting in either cell necrosis, fibrosis, or fatty infiltration is known to be a widespread phenomenon, potentially of importance to human health. It is caused by numerous drugs and environmental agents, and its incidence is expected to increase as confounding viral liver disease becomes more prevalent. Much is known about mechanisms based upon comprehensive studies with a few prototypical chemicals—namely, CCb, ethanol and acetaminophen—which support a convergence of varied primary effects on the ultimate failure of mitochondrial function and Ca2+ homeostasis. The extensive metabolic activity of the liver exposes its cells to a continuous flux of prooxidants. The importance of metabolic activation for the production of reactive metabolites is well-... 

Hydrocodone, another codeine congener, is approximately six times more potent than codeine. This agent appears to cause less constipation and less sedation than codeine. It has been suggested that hydrocodone may produce more euphoria than codeine, but this effect has not been substantiated in clinical studies. Hydrocodone is also available in combination with aspirin, acetaminophen, or ibuprofen. 

Pain killers and anti-inflammatory agents may also cause a problem. Watch out for acetaminophen (Tylenol), naproxen (OTC Aleve or Rx Naprosyn), and ibuprofen (Advil, Motrin). The prescription-only anti-inflammatory drugs diclofenac (Voltaren) and indomethacin (Indocin) can also increase blood pressure. 

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