The study of drugs and their interaction in human bodies is called pharmacology, and comes from pharmakon, a Greek word meaning drug or medicine and logy meaning a study of. In other words, pharmacology can also be termed as a study of either drugs or medicine, and examines their origin, their nature, their reactions in the body as well as side effects (Turley, 2003). The discussion hereunder will focus on different types of drugs that are used to relieve pain, their mechanism as well as their side effects.
Types of drugs used to relieve pain ((Turley, 2003)
Over-the-counter (OTC): These are drugs used to relieve pain, and one can use without necessarily considering a prescription from a doctor. Under OTC, there is;
Acetaminophen, which increases the threshold of pain in the body, and
Nonsteroidal anti-inflammatory drugs (NSAIDs) that relieves pain by acting on those substances that cause pain and inflammation in the body
Corticosteroids relieve musculoskeletal injuries by providing an anti-inflammatory effect
Narcotic analgesics also referred to as opioids alter any message of pain in the brain
Anticonvulsant drugs that stabilize nerve cells, thereby reducing neuropathy pain
Antidepressants relieve pain that is transmitted via the spinal cord
Muscle relaxants reduce muscular pain
Anti-anxiety drugs lower anxiety, help the muscles relax and then helps to accommodate the discomfort
Mechanism of Acetaminophen
Its mechanism is a bit simple because it is focused on the parts of the brain that receive pain-related messages, and also manages the temperature in the body. It might be categorized under analgesics, and lowers the production of prostaglandins known to induce swelling as well as inflammation in the brain, and acts by raising the pain threshold thus relieving pain. In simpler terms, the action of Acetaminophen is dependent on the central nervous system (CNS) where after increasing the pain threshold, it prevents the isoforms of cyclooxygenase, as well as the enzymes COX-1, COX-2, and COX-3, thereby initiating the synthesis of prostaglandin (PG). It also blocks COX indirectly, although the block is not effective where peroxide is present, and this makes it effectual in CNS as well as endothelial cells (Turley, 2003).
Therapeutic efficacy
Acetaminophen is used to relieve mild pain but can be used to relieve severe pain especially when used in combination with opioid pain medication. It can be used in one of the following ways; rectally, intravenously or by mouth, and its effect can only last between 2-4 hours. When used at the recommended doses, Acetaminophen is safe to the user, although high doses lead to liver failure as well as skin rashes. On top of that, it can effectively be used during pregnancy, breastfeeding and by people with liver disease, although in reduced doses (Turley, 2003).
Adverse effect and abuse potential
As stated, Acetaminophen causes skin rashes and acute liver failure, and these are the most common adverse effects of this drug. On the other hand, the abuse potential comes in when people suffering from headache or any other type of pain may take overdose for quick action. Besides, another abuse potential well-known particularly in United States is taking too much of it with an intention of getting high, as well as taking it together with other drugs with traces of Acetaminophen (Forte, 2002).
Acetaminophen toxicities
The metabolism of Acetaminophen takes place in the liver, and by the help of its conjugation and glucoronic acid, it is converted into inactive compounds. The liver excretes the conjugates while part of it is oxidized through the enzyme known as CYP2E1 to give N-acetyl-p-benzoquinoneimine (NAPQI) which is toxic. Therefore, the toxic effect of acetaminophen is as a result of NAPQI which in most cases occurs due to overdose (Forte, 2002).
In conclusion, acetaminophen can be used effectively to relieve pain as well as headache and other aches. Besides, people suffering from arthritis and chronic problems can use it, but it should only be used as described, to avoid overdose that can lead to adverse body effects.
References
Forte, J. S. (2002). Paracetamol: safety versus toxicity. The Chronic ill, 6, 12-16.
Turley, S. M. (2003). Understanding Pharmacology for Health Professionals. Prentice-Hall.
