Products
Caffeine citrate solution was newly approved in many countries in 2016 (Peyona). It was available earlier in other countries.
Structure and properties
Caffeine (C8H10N4O2, Mr = 194.2 g/mol) exists as a white crystalline powder or as white silk-like crystals and is sparingly soluble in water. The substance sublimes readily. Citric acid monohydrate (C6H8O7 – H2O, Mr = 210.1 g/mol) exists as a white crystalline powder, colorless crystals or granules and is very soluble in water. It is added to increase the solubility of caffeine.
Effects
Caffeine (ATC N06BC01) is analeptic. It stimulates the central nervous system, the respiratory center, and thus respiration. The effects are due to antagonism at adenosine receptors.
Indications for use
For the treatment of respiratory failure in premature infants (apnea of prematurity).
Dosage
According to the SmPC. The solution is administered in the intensive care unit as a slow intravenous infusion or perorally by nasal tube. The instructions in the SmPC must be followed carefully to avoid overdose. For example, the half-life of caffeine in preterm infants is greatly prolonged, lasting several days.
Contraindications
Caffeine citrate is contraindicated in hypersensitivity. Full precautions can be found in the drug label.
Interactions
Caffeine is metabolized by CYP1A2. However, liver metabolism is still insufficiently developed in premature infants. Drug-drug interactions may occur with cimetidine, ketoconazole, phenobarbital, phenytoin, doxapram, H2 antihistamines, and proton pump inhibitors, among others. Caffeine should not be co-administered with theophylline.
Adverse effects
Possible adverse effects include local reactions at the site of administration, stimulation of the central nervous system (nervousness, irritability, restlessness), rapid heartbeat, hypertension, vomiting, and hypersensitivity reaction. Whether there is an association between administration and the development of necrotizing enterocolitis is controversial.