Drug Interactions between stiripentol and Synalgos-DC

GENERALLY AVOID: Taking stiripentol on an empty stomach may reduce its oral bioavailability. Stiripentol degrades rapidly when exposed to gastric acid in an empty stomach.

GENERALLY AVOID: Alcohol may potentiate the depressant effects of stiripentol on the central nervous system. Concomitant use may result in increased sedation and dizziness as well as impairment of psychomotor skills.

GENERALLY AVOID: It is not known whether stiripentol may reduce theophylline and caffeine metabolism, as data on the potential for inhibition of CYP450 1A2 are limited. Consumption of foods and nutritional products such as cola drinks (which contain significant quantities of caffeine) and chocolate (which contains caffeine and trace amounts of theophylline) may be unsafe during treatment with stiripentol, particularly in children.

MANAGEMENT: Stiripentol should be taken during a meal for optimal absorption; however, it should not be taken with milk, dairy products (e.g., yogurt, soft cream cheese), fruit juice, or carbonated beverages. Patients should be advised to avoid or limit consumption of alcohol and to avoid activities requiring mental alertness such as driving or operating hazardous machinery until they know how the medication affects them. Food and beverages that may contain caffeine or theophylline such as colas, chocolate, coffee, tea, or energy drinks should also be avoided during treatment with stiripentol.

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.

The effect of grapefruit juice on the pharmacologic activity of caffeine is controversial. One report suggests that grapefruit juice increases the effect of caffeine. The proposed mechanism is inhibition of cytochrome P-450 metabolism of caffeine. However, a well-conducted pharmacokinetic/pharmacodynamic study did not demonstrate this effect. The clinical significance of this potential interaction is unknown.

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.