Pain reliever: what is it?

Pain reliever (or analgesic) is a medicine that prevents or decreases the feeling of pain. The most common pain relievers over the counter areaspirin, paracetamol andibuprofen.

Medical research is interested in molecules present in venoms animals that could become the painkillers of tomorrow. This is the case, for example, of coral snake venom, black mamba (a cobra) or a tropical fish, Meiacanthus grammists.

Use of analgesics in human medicine

Analgesics are divided into three classes defined by the WHO, depending on their potency:

• the analgesics level I for mild to moderate pain: aspirin, paracetamol, nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen;
• level II analgesics, for moderate or severe pain which is not relieved by level 1 analgesics: codeine, tramadol, etc.;
• level III analgesics, for severe pain which are resistant to other analgesics: morphine, opium derivatives (fentanyl, oxycodone, etc.). Opiates work by attaching to receptors opioids present in the central nervous system.

The doctor, before prescribing an analgesic, should assess the patient’s pain level. It is important to follow your doctor’s prescription during treatment, in order to avoid overdoses. For example, paracetamol can be taken in a dose of 500 mg to 1 g every four to six hours, without exceeding three grams per day. Some pain relievers are not recommended during pregnancy,feeding with milk, or in patients with other pathologies (epilepsy, asthma…).