Linezolid thrombocytopenia with

When linezolid is used with antiplatelet drugs such as aspirin or die NSAIDs (see Chap. 18) diere is an increased risk of bleeding and thrombocytopenia When administered widi die MAOIs (see Chap. 31) the effects of the MAOIs are decreased. There is a risk of severe hypertension if linezolid is combined widi large amounts of food containingtyramine (eg, aged cheese, caffeinated beverages, yogurt, chocolate, red wine, beer, pepperoni). 

Myelosuppression Myelosuppression (including anemia, leukopenia, pancytopenia, and thrombocytopenia) has been reported in patients receiving linezolid. Monitor complete blood counts weekly in patients who receive linezolid, particularly in those who receive linezolid for more than 2 weeks, those with preexisting myelosuppression, those receiving concomitant drugs that produce bone marrow suppression, or those with a chronic infection who have received previous or concomitant antibiotic therapy. 

Thrombocytopenia - Linezolid has been associated with thrombocytopenia when used in doses of 600 mg or less every 12 hours for up to 28 days. Thrombocytopenia associated with the use of linezolid appears to be dependent on duration of therapy (generally more than 2 weeks of treatment). The platelet counts for most patients returned to the normal range/baseline during the follow-up period. 

The principal toxicity of linezolid is hematologic—reversible and generally mild. Thrombocytopenia is the most common manifestation (seen in approximately 3% of treatment courses), particularly when the drug is administered for longer than 2 weeks. Anemia and neutropenia may also occur, most commonly in patients with a predisposition to or underlying bone marrow suppression. Cases of optic and peripheral neuropathy and lactic acidosis have been reported with prolonged courses of linezolid. These side effects are thought to be related to linezolid-induced inhibition of mitochondrial protein synthesis. 

Observational studies The safety of prolonged treatment with linezolid (>4 weeks), alone or in combination with rifam-picin, has been assessed in a retrospective study in 94 subjects with bone and joint infections [83 ]. Major adverse events included anemia (30%), thrombocytopenia... 

Niwa T, Suzuki A, Sakakibara S, Kasahara S, Yasuda M, Fukao A, Matsuura K, Goto C, Murakami N, Itoh Y. Retrospective cohort chart review study of factors associated with the development of thrombocytopenia in adult Japanese patients who received intravenous linezolid therapy. Clin Ther 2009 31(10) 2126-33. 

A cohort study investigating the incidence of thrombocytopenia in subjects receiving linezolid reported a rate of critical thrombocytopenia (<20,000 cells/nun) of 0.8%. A >50% decline in platelets was seen in 17.1% of patients. High trough concentrations were associated with an increased risk of low platelets [79 ]. This is supported somewhat by a retrospective case study which noted a rate of thrombocytopenia of (27.2%) in adult Chinese patients. Multivariate analysis noted that a daily dose of linezolid of >18.75mg/kg, a baseline platelet count of <181 x 10 /L, therapy >10 days and concomitant use of caspofungin and levofloxacin as predictors for low platelets with linezolid treatment [12H]. 

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