10 Dec 2010 An analgesic is any member of the medicinal drug that is used to relieve pain and to achieve analgesia. It belongs to the group of painkilling medicine or pain killers. Derived from the Greek Word "an-" meaning "without" and "algia-" meaning "pain". Analgesic drugs are classified into following groups depending on their usage and application related to various types of pain. Doctors take into account a variety of factors, like the cause of pain and its severity, in order to choose the appropriate analgesic for a patient.
The most common analgesics belong to the nonsteroidal anti-inflammatory drugs (NSAIDs). They are easily available as over-the-counter medications in chemist shops. Important medicines include ibuprofen (Motrin), naproxen (Aleve) and Aspirin. These drugs have the ability to relieve pain. They can reduce fever and suppress inflammation.
They work by blocking cyclooxygenase (COX), an enzyme in various tissues that produce the chemical mediators which are the cause for inflammation, related pain, and fever. Aspirin besides acting as a pain killer also has anti-platelet properties, which helps in the treatment for heart attacks and strokes. There is another analgesic by the trade name Tylenol, which reduces pain and fever but not inflammation, and hence not included in the NSAID class.
Corticosteroids are not exactly pain killing medicines but they are anti-inflammatory. But due to their inflammatory processes, they can reduce pain. For example, a patient with arthritis may be relieved from injections of steroids into the inflamed joint.
The opioid analgesics relieve pain by binding to opioid receptors in the central nervous system. They are also known as narcotics. Popular ones are morphine, fentanyl, and oxycodone. These drugs act as agonists to produce the effect of analgesia. Opioids give relief for moderate to severe pain. However, there is also the risk for potential addiction in some patients. Narcotics are stronger analgesics. They are used when pain is too severe to be controlled by NSAID analgesics. All narcotic analgesics are prescription medications.
There are certain drugs that are mainly used for neurologic and psychiatric conditions but they can also relieve neuropathic pain, which occurs without any external pain triggers like heat or sharp points. Neuropathic anlagesia drugs include the antidepressant amitriptyline (Elavil) and the anticonvulsant gabapentin (Neurontin).
Pain relief at times is required with a nerve blockade. An anesthetic drug, like lidocaine, can be injected into a nerve branch so that a certain part of the body becomes desensitized to pain. For example, anesthetic injection around the spinal cord produces pain relief in areas in the lower half of the body.