BACKGROUND Metamizole is used to treat pain in many parts of the world. Information on the safety profile of metamizole is scarce; no conclusive summary of the literature exists. OBJECTIVE To determine whether metamizole is clinically safe compared to placebo and other analgesics. METHODS We searched CENTRAL, MEDLINE, EMBASE, CINAHL, and several clinical trial registries. We screened the re...

Metamizole [INN; dipyrone (BAN, USAN)] is a pyrazolone derivative and one of the most commonly prescribed analgesics worldwide (1). Along with non-steroidal anti-inflammatory drugs (NSAIDs), metamizole is very frequently involved in hypersensitivity reactions (2). Immunologically mediated hypersensitivity reactions to metamizole can be immediate (IgE-mediated) or non-immediate (T cell-mediated)...

A 4-year-old boy presented with fever, septic arthritis, and persistent neutropenia. Bone marrow biopsy revealed no evidence of neoplasia. Additional history disclosed that the patient had been given metamizole for pain before onset of his illness. Metamizole, a nonsteroidal antiinflammatory agent, is prohibited in the United States because of the risk of agranulocytosis but is widely used in M...

PURPOSE Nonsteroidal anti-inflammatory drugs (NSAIDs) play an important role in multimodal pain management. In patients with a contraindication for NSAIDs, pain management is challenging. A recent Dutch anesthesiology guideline propagates the use of metamizole (dipyrone) in these patients. Metamizole is a controversial drug, its use being previously discouraged because of the risk for agranuloc...

Metamizole (dipyrone) is a popular analgetic, non-opioid drug, commonly used in human and veterinary medicine. In some cases, this agent is still incorrectly classified as a non-steroidal anti-inflammatory drug (NSAID). Metamizole is a pro-drug, which spontaneously breaks down after oral administration to structurally related pyrazolone compounds. Apart from its analgesic effect, the medication...

Metamizole, a non-steroidal anti-inflammatory drug with weak anti-inflammatory and spasmolytic effects, is used as an analgesic and antipyretic agent. Many adverse reactions to metamizole, such as early or late-onset systemic reactions and bone marrow suppression, have been identified. In this report, we present a case of systemic reaction after the application of parenteral metamizole (Novalgi...

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most common cause of hypersensitivity reactions, with pyrazolones the most frequent drugs inducing selective reactions. Immediate selective hypersensitivity to pyrazolones is thought to be mediated by specific-IgE. Sensitivity of in vitro diagnostic tests is low and this may be due to the incomplete characterization of the structures involv...

BACKGROUND Metamizole is one of the pyrazolone drugs used widely in Turkey. The aim of this survey was to determine the clinical features of metamizole intolerant patients and to find out if there was any difference between the ones with or without bronchial asthma. METHODS A total of 264 patients with metamizole intolerance were enrolled in the survey. Patients having bronchial asthma were a...

Cutaneous adverse reactions to benzodiazepines seem to be rare. We report a 61-year-old man with adverse reactions after ingestion of metamizole, diclofenac, and tetrazepam. Skin prick tests with metamizole, diclofenac, and tetrazepam were negative. Patch tests with metamizole, diclofenac, and tetrazepam (all at 5% in aqueous solution) were performed, and were positive for tetrazepam. Oral chal...

BACKGROUND Pyrazolones are the most common causes of selective nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity. We studied a large group of patients with immediate and delayed selective responses to metamizole. METHODS Patients with suspicion of hypersensitivity to metamizole were evaluated. We verified acetylsalicylic acid tolerance and classified patients as immediate or delaye...