Drug Interaction Report

ADJUST DOSING INTERVAL: Food may increase the extent of tecovirimat absorption following oral administration. When the recommended oral dose of tecovirimat (600 mg every 12 hours) was administered with a meal (approximately 600 calories and 25 g of fat) in healthy adults weighing less than 120 kg, tecovirimat absorption increased by 39% relative to fasting.

MANAGEMENT: Oral tecovirimat should be taken within 30 minutes after a full meal containing moderate or high fat (approximately 600 calories and 25 g of fat) with 6 to 8 ounces of water.

MONITOR: Two cases have been reported in which patients on sulfamethoxazole-trimethoprim therapy, after consuming beer, reported flushing, heart palpitations, dyspnea, headache, and nausea (disulfiram - alcohol type reactions). First-generation sulfonylureas have been reported to cause facial flushing when administered with alcohol by inhibiting acetaldehyde dehydrogenase and subsequently causing acetaldehyde accumulation. Since sulfamethoxazole is chemically related to first-generation sulfonylureas, a disulfiram-like reaction with products containing sulfamethoxazole is theoretically possible. However, pharmacokinetic/pharmacodynamic data are lacking and in addition, the two reported cases cannot be clearly attributed to the concomitant use of sulfamethoxazole-trimethoprim and alcohol.

MANAGEMENT: Patients should be alerted to the potential for this interaction and although the risk for this interaction is minimal, caution is recommended while taking sulfamethoxazole-trimethoprim concomitantly with alcohol.