Paracetamol (also known as acetaminophen) is a household name, and it is used to treat a variety of ailments. Being available without a prescription, it is one of the most popular analgesic drugs in the world. Paracetamol is a favorable choice for conditions that cannot be treated with non-steroidal anti-inflammatory drugs (such as ibuprofen), including asthma and hemophilia. On the whole, paracetamol is a well-tolerated drug and is often the recommended first-line treatment for conditions such as osteoarthritis.
How does paracetamol work?
Despite paracetamol being commonly used for a variety of acute and chronic conditions, its mechanism of action still is not fully understood. Paracetamol causes analgesic effects through the activation of specific pathways in the body. It is thought that pain is reduced through a decrease in the production of prostaglandins in the brain and spinal cord. When the body experiences an injury or disease, prostaglandins are released by the body to make nerve endings sensitive to create pain. This way, we are discouraged from causing more harm to the affected part of the body. Therefore, if paracetamol decreases the number of prostaglandins, the nerve cells will not be as sensitive, and pain will be decreased.
Paracetamol is also thought to affect nitric oxide and opioid pathways in the body. It is likely that it uses a combination of various pathways to increase the pain threshold. One such pathway thought to be altered by paracetamol is the serotoninergic pathway. This pathway is a part of the descending pain system which starts in the brainstem. There are serotonin receptors dotted all over the central nervous system, which have multiple functions including controlling mood and memory. It is widely believed that the activation of serotonergic pathways plays an important role in the action of paracetamol. Which is crucial.
How efficient is paracetamol?
When compared to standard doses of many non-steroidal anti-inflammatory drugs, paracetamol has similar efficacy, whilst showing fewer side effects. When administered intravenously, paracetamol acts much faster than when taken orally. However, a study has suggested that there is no difference in efficacy between the two routes.
Whilst paracetamol is widely considered safe, there is an extensive list of potential side effects. These include skin rashes, increased serum glucose, and decreased concentrations of sodium and calcium. Paracetamol administration has also been associated with liver failure, and in some cases has led to liver transplantations. Damage to the liver has been linked to doses that exceed the recommended maximum dose. Damage has also been observed alongside chronic dosing of paracetamol.
In the United States alone, paracetamol is thought to be responsible for 500 deaths per year, with it being the most common drug-related cause of acute liver failure. When an excessive dose is administered, metabolism pathways are affected, causing them to not function correctly. It should be noted that the majority of patients who receive an overdose of paracetamol do not show symptoms in the first few hours following ingestion. Abdominal pain and nausea are present within the first 12 to 24 hours.