What is Analgin?
Metamizole (INN), or dipyrone (BAN, USAN), is an ampyrone sulfonate analgesic (pain reliever), antispasmodic (spasm reliever) and antipyretic (fever reducer) similar to paracetamol in that it has minimal anti-inflammatory effects and which is most commonly given orally or parenterally (by injection) to prevent and treat pain related to surgery or for the treatment of acute pain. although in some countries it is available over-the-counter, its use is usually restricted in developed countries, due to its potential for causing toxic reactions.
Metamizole is marketed under various trade names, including Algozone, Algocalmin, Algopyrin, Analgin, Dipirona, Novalgin, Neo-Melubrina and Optalgin.
It was once widely combined with various other active ingredients, but since concerns over its safety have been raised in the late 1960s and 1970s its use in combination products has been in decline and in some countries, banned. Regardless, some national medical authorities (such as in Australia and United States of America) have withdrawn metamizole from the market altogether or have restricted it to be available only with a prescription, although it remains available over the counter in some countries.
Despite its potential haematologic (blood-related) toxicity (that is potential for causing blood dyscrasias) it produces no clinically relevant effects in the way of kidney toxicity, cardiovascular toxicity and GI toxicity when compared to non-steroidal anti-inflammatory drugs (NSAIDs). Unlike paracetamol and similarly to the NSAIDs it can trigger bronchospasm or anaphylaxis, especially in those with asthma.