The pharmacological characteristics of clonazepam are similar to those of benzodiazepines, and they include anticonvulsant, sedative, muscle relaxant, and anxiolytic actions. Its effects are thought to be predominantly caused by GABA-mediated postsynaptic inhibition, similar to other benzodiazepines, while some animal studies also indicate a serotonin impact.

Clonazepam quickly suppresses many types of paroxysmal activity, including spike-and-wave discharge in absence seizures (petit mal), slow spike waves, slow spike waves, generalized spikes, spikes with temporal or other locations, as well as irregular waves and spikes, according to data from animal models and some electroencephalographic studies in humans.

Compared to localized abnormalities, generalized EEG normalities are repressed more frequently. Clonazepam shows positive benefits in both generalized and focal epilepsies, which is consistent with this.

The digestive system effectively absorbs clonazepam. In one investigation, when a single 2 mg oral dose of micronized clonazepam was given to healthy persons, the peak blood concentrations found after 1 to 2 hours ranged from 6.5-13.5 ng/mL. The greatest concentration, however, was discovered in some people between 4 and 8 hours. Although the level of clonazepam in plasma necessary to produce a therapeutic effect has not been determined, several research suggest that it may range from 20 to 80 ng/ml. For adults, clonazepam 6 mg daily in three split doses and for children aged 6 to 13 years, clonazepam 1.5–4 mg daily in three divided doses can be used to maintain plasma concentrations in this range. The action often begins between 20 and 60 minutes. Infants and young children experience it for 6 to 8 hours, whereas adults experience it for more than 12 hours.

The distribution of clonazepam is not well understood, however it is comparable to that of other benzodiazepines. The blood-brain barrier and the placenta both seem to be crossed by the medication.

The liver breaks down clonazepam into a number of metabolites, including clonazepam, 7-aminoclonazepam, 7-acetaminoclonazepam, and their 3-hydroxy derivatives. The metabolites of clonazepam, along with their glucuronic and/or sulphate conjugates, are primarily eliminated in the urine by a first order reaction. Only a small portion of the medication is excreted unaltered.