Drug Interactions between cycloserine and Jynarque

GENERALLY AVOID: Coadministration with alcohol may potentiate some of the central nervous system adverse effects of cycloserine and its prodrug, terizidone. These effects may include dizziness, drowsiness, depression, anxiety, psychoses, memory impairment, confusion, and convulsions.

MANAGEMENT: Patients should be advised to avoid the consumption of alcohol during treatment with cycloserine or terizidone. The use of these medications is contraindicated in patients with chronic alcohol consumption or alcoholism.

MONITOR CLOSELY: Coadministration with caffeine may potentiate some of the central nervous system adverse effects of cycloserine and its prodrug, terizidone. These effects may include insomnia, excitability, irritability, anxiety, tremor, psychoses, and convulsions.

MANAGEMENT: Caution is advised when cycloserine or terizidone is used with caffeine. Consumption of certain beverages or stimulants with very high caffeine levels should be avoided as a precautionary measure.

GENERALLY AVOID: Grapefruit juice may significantly increase the plasma concentrations of tolvaptan. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. According to the product labeling, administration of tolvaptan with grapefruit juice resulted in a 1.8-fold increase in tolvaptan systemic exposure. The clinical significance is unknown, although increased pharmacologic effects may be expected. Too rapid correction of hyponatremia increases the risk of osmotic demyelination syndrome, which is associated with dysarthria, mutism, dysphagia, lethargy, affective changes, spastic quadriparesis, seizures, coma, and death.

MANAGEMENT: Patients treated with tolvaptan should avoid consumption of grapefruits and grapefruit juice.