Peak plasma concentrations are attained two hours after bromazepam is administered orally. The tablet has a 60% absolute and 100% relative bioavailability when compared to an IV solution and an oral solution, respectively.

Distribution: Plasma proteins bind around 70% of the bromazepam that is taken orally. The distribution contains 50 litres.

Metabolism: Cytochrome P450 (CYP450) is used in the liver to partially metabolize bromazepam. The precise CYP isoenzymes implicated, however, are still unknown. Quantitatively, 3-hydroxybromazepam, which has less action than bromazepam, and 2-(2-amino-5-bromo-3-hydroxybenzoyl) pyridine, which has no effect, are the two main metabolites.

Elimination: 2, 27, and 40% of the administered dose of the glucuronide conjugates of 3-hydroxybromazepam and 2-(2-amino-5-bromo-3-hydroxybenzoyl)pyridine as well as intact bromazepam are recovered in the urine, respectively. The half-life of bromazepam’s elimination is about 20 hours. 40 ml/min is the clearance.

Drug kinetics in particular populations:

Elderly: In elderly patients, the elimination half-life may be extended. An elderly patient would often have roughly twice the steady-state concentrations of bromazepam in any dosage range compared to a younger patient.

Pharmacodynamics:

Benzodiazepines’ central effects are mediated by an increase in GABAergic neurotransmission at inhibitory synapses. Positive allosteric modulation, which occurs in the presence of benzodiazepines, increases the affinity of the GABA receptor for the neurotransmitter, increasing the effect of released GABA on the postsynaptic transmembrane flow of chloride ions.

Bromazepam selectively lessens tension and anxiety when used in small doses. Sedative and muscle-relaxing effects only appear at large doses.