Drug Interaction Report

ADJUST DOSING INTERVAL: Administration of a tetracycline with aluminum, calcium, or magnesium salts significantly decreases tetracycline serum concentrations. The proposed mechanism is chelation of tetracycline by the cation, forming an insoluble complex that is poorly absorbed from the gastrointestinal tract. The interaction has also been reported with parenteral doxycycline and oral antacids.

MANAGEMENT: The administration of tetracyclines and preparations containing aluminum, magnesium, or calcium should be separated by two to four hours. When coadministered with Suprep Bowel Prep (magnesium/potassium/sodium sulfates), the manufacturer recommends administering tetracycline antibiotics at least 2 hours before and not less than 6 hours after Suprep Bowel Prep to avoid chelation with magnesium.

ADJUST DOSING INTERVAL: Administration with food, particularly dairy products, may reduce the absorption of omadacycline. The calcium content of these foods may form nonabsorbable chelates with omadacycline.

MANAGEMENT: Omadacycline should be administered at least 2 hours before (4 hours for dairy products) or 4 hours after meals.

GENERALLY AVOID: Use of anticholinergic agents with alcohol may result in sufficient impairment of attention so as to render driving and operating machinery more hazardous. In addition, the potential for abuse may be increased with the combination. The mechanism of interaction is not established but may involve additive depressant effects on the central nervous system. No effect of oral propantheline or atropine on blood alcohol levels was observed in healthy volunteers when administered before ingestion of a standard ethanol load. However, one study found impairment of attention in subjects given atropine 0.5 mg or glycopyrrolate 1 mg in combination with alcohol.

MANAGEMENT: Alcohol should generally be avoided during therapy with anticholinergic agents. Patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them.

GENERALLY AVOID: The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss. The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

MANAGEMENT: Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.