A case of tramadol induced anaphylactic shock

Tramadol is a centrally acting analgesic and has serotonergic and noradrenergic action. The metabolite of Tramadol is O-desmethyltramadol and acts on the µ-opioid receptor. It is 10 times less potent then morphine. Tramadol is used to treat both acute and chronic pain of moderate intensity. Tramadol is considered to be a relatively safe analgesic. Commonadverse effects of tramadol are nausea, dizziness, and vomiting, particularly at the start of the therapy. At therapeutic doses, tramadol does not cause respiratory depression, however, in patients with diminished respiratory function and who are taking additional Benzodiazipine drugs it may cause respiratory depression and hence not advisable. Orally administered tramadol can produce opioid-like effects (both mentally and physically but these effects are mild and not produced following parenteral administration. Fatal intoxications are rare and appear to be associated with large overdoses of tramadol and co-ingestion of other drugs (including alcohol). Tramadol is used worldwide and is listed as a step-2 analgesic in the WHO guidelines for cancer pain relief. Tramadol is also listed on several national essential medicines lists. Tramadol was first synthesized in 1962 by Grünenthal GmbH in Germany by coupling of the corresponding cyclohexanon with 3-methoxyphenylmagnesium bromide in a Grignard reaction.(1:2) Tramadol shows structural resemblance with codeine and both have a 3-methoxy group on the phenyl ring. Tramadol hydrochloride is readily soluble in water and methanol. Mechanism of Action The (+)-enantiomer of tramadol contributes to analgesia by inhibiting the reuptake of serotonin, the (-)-enantiomer by inhibiting the reuptake of noradrenaline, and the O-desmethyl metabolite by binding with relative high affinity to the µ-opioid receptor (4). Tramadol binds with low affinity to the human µ-opioid receptor. This affinity is approximately 4000-fold less than that of morphine (3:4) There are less chances of anaphylaxis to Tramadol. The Allergy Unit, Department of Paediatrics, University of Florence, Anna Meyer Children's University Hospital, Florence, Italy reported a case of Anaphylaxis to Tramadol in a child in 2015.No more cases of Anaphylaxis reaction to Tramadol are found in the literature We are reporting here a case of anaphylactic shock after intravenous injection of tramadol hydrochloride in emergency department.