Drug Interactions between Ascomp with Codeine and dasatinib

GENERALLY AVOID: Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants (e.g., nonbenzodiazepine sedatives/hypnotics, anxiolytics, muscle relaxants, general anesthetics, antipsychotics, other opioids, alcohol) may result in profound sedation, respiratory depression, coma, and death. The risk of hypotension may also be increased with some CNS depressants (e.g., alcohol, benzodiazepines, phenothiazines).

MANAGEMENT: The use of opioids in conjunction with benzodiazepines or other CNS depressants should generally be avoided unless alternative treatment options are inadequate. If coadministration is necessary, the dosage and duration of each drug should be limited to the minimum required to achieve desired clinical effect, with cautious titration and dosage adjustments when needed. Patients should be monitored closely for signs and symptoms of respiratory depression and sedation, and advised to avoid driving or operating hazardous machinery until they know how these medications affect them. Cough medications containing opioids (e.g., codeine, hydrocodone) should not be prescribed to patients using benzodiazepines or other CNS depressants including alcohol. For patients who have been receiving extended therapy with both an opioid and a benzodiazepine and require discontinuation of either medication, a gradual tapering of dose is advised, since abrupt withdrawal may lead to withdrawal symptoms. Severe cases of benzodiazepine withdrawal, primarily in patients who have received excessive doses over a prolonged period, may result in numbness and tingling of extremities, hypersensitivity to light and noise, hallucinations, and epileptic seizures.

MONITOR CLOSELY: Coadministration of dasatinib and drugs that interfere with platelet function or coagulation may potentiate the risk of bleeding complications. Treatment with dasatinib is associated with severe thrombocytopenia. In addition, dasatinib has been shown to induce platelet dysfunction in vitro. Severe central nervous system hemorrhages, including fatalities, occurred in 1% of patients receiving dasatinib in clinical trials. Severe gastrointestinal hemorrhage occurred in 7% of patients and generally required treatment interruptions and transfusions. Other cases of severe hemorrhage occurred in 4% of patients. Most bleeding events were associated with severe thrombocytopenia.

MANAGEMENT: Concomitant use of other medications that interfere with platelet function or coagulation should be considered cautiously in patients treated with dasatinib. Close clinical and laboratory observation for bleeding complications is recommended during therapy. A complete blood count (CBC) with differential and platelet count should be obtained prior to and at least weekly for the first 2 months, then monthly thereafter or as clinically indicated. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

MONITOR: Coadministration with inducers of CYP450 3A4 may decrease the plasma concentrations of dasatinib, which is primarily metabolized by the isoenzyme. When a single morning dose of dasatinib was administered to 20 healthy subjects following 8 days of continuous evening dosing of 600 mg rifampin, a potent CYP450 3A4 inducer, mean dasatinib peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 81% and 82%, respectively, compared to dasatinib administered alone. The extent to which other, less potent CYP450 3A4 inducers may interact with dasatinib is unknown.

MANAGEMENT: The potential for diminished pharmacologic effects of dasatinib should be considered during coadministration with CYP450 3A4 inducers. Alternative treatments may be required if an interaction is suspected, or a dosage increase for dasatinib depending on patient tolerability. Close monitoring for toxicities (e.g., myelosuppression, bleeding complications, fluid retention, QT prolongation) is recommended if the dosage of dasatinib is increased. The dosage should be reduced to the indicated dosage following discontinuation of the potent CYP450 3A4 inducer.

One study has reported that coadministration of caffeine and aspirin lead to a 25% increase in the rate of appearance and 17% increase in maximum concentration of salicylate in the plasma. A significantly higher area under the plasma concentration time curve of salicylate was also reported when both drugs were administered together. The exact mechanism of this interaction has not been specified. Physicians and patients should be aware that coadministration of aspirin and caffeine may lead to higher salicylate levels faster.