Tramadol drug interactions

Tramadol 50-100 mg every 4-6 hours not to exceed 400 mg/day has narcotic-like effect contraindicated in alcohol or hypnotic intoxication drug interactions expensive... 

Drug-drug interactions Coadministration of tramadol with vitamin K antagonists increases INR [81 ]. Findings were confirmed by a case-control trial assessing patients on tramadol who were placed on a vitamin K antagonist [82 ]. Patients on rifampicin experienced decreased oral bioavailability of lOO-mg tramadol and decreased durabon of acHon of intravenous 50-mg tramadol [83 -]. A case series of two elderly women on 100-mg oral tramadol demonstrated acute onset of hallucinations after administration of influenza vaccine [84 ]. 

PunwaniNG. Tramadol pharmacokinetics and itspossible interactions with cyclooxygenase 2-selective nonsteroidal anti-inflammatory drugs. CUn Pharmacol Ther lQOA) 75,363-5. 

Similarly, seizures and the serotonin syndrome have been reported in a woman who took mirtazapine with tramadol, but this may have been due to over-use of the tramadol rather than an interaction. Lethargy, confusion, hypotension, bronchospasm and hypoxia has also been seen following the use of tramadol and mirtazapine, which resolved within hours of both drugs being stopped. ... 

In a retrospective cohort study of patients taking acenocoumarol or phenprocoumon, tramadol was found to be assoeiated with a threefold increased risk of bleeding. The study was speeifieally looking at potentially interacting drugs taken by at least 50 patients and with at least 5 eases of bleeding. ... 

The Australian Adverse Drug Reaction Advisory Committee has stated that tramadol may cause the serotonin syndrome, particularly when it is used at high doses or in combination with other drugs increasing serotonin le vel s of 20 reported cases of the serotonin syndrome associated with tramadol, 16 were taking potentially interacting medicines including SSRIs. Cases of the serotonin syndrome with specific SSRIs are discussed below. 

Because of the possible increased risk of seizures, tramadol should be used with caution in patients taking drugs such as the SSRIs, which can lower the seizure threshold. The concurrent use of tramadol and SSRIs may also lead to an increase in serotonin-associated effects, which can include the serotonin syndrome. However, the relatively few reported cases of the serotonin syndrome or other reactions due to an interaction between an SSRI and tramadol need to be set in the wider context of apparently uneventful and advantageous use in other patients,although some workers have suggested that the incidence of serotonin syndrome may be underreported. There would seem to be little reason for totally avoiding the concur-... 

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