From the Research
Valium (diazepam) typically begins working within 15 to 60 minutes when taken orally, with peak effects occurring between 1 to 2 hours after administration. The onset of action varies depending on the route of administration: intravenous diazepam acts almost immediately (within 1-5 minutes), while intramuscular injection has a slower and less predictable onset of about 15-30 minutes 1. This rapid onset is due to diazepam's high lipid solubility, allowing it to quickly cross the blood-brain barrier and bind to GABA receptors in the central nervous system, as discussed in the study on midazolam and other benzodiazepines 2.
The effects of diazepam are a result of its potentiation of the neural inhibition mediated by gamma-aminobutyric acid (GABA), leading to sedation, hypnosis, decreased anxiety, anterograde amnesia, centrally mediated muscle relaxation, and anti-convulsant activity 2. Patients should be aware that the medication may cause drowsiness, impaired coordination, and cognitive effects soon after taking it, so they should avoid driving or operating machinery until they know how the medication affects them.
Some key points to consider when administering diazepam include:
- The duration of action for a single dose is typically 6-8 hours, though some effects may persist longer due to diazepam's active metabolites 1.
- Diazepam has a dose-dependent ventilatory depressant effect and can cause a modest reduction in arterial blood pressure and an increase in heart rate as a result of a decrease of systemic vascular resistance 2.
- The medication should be used with caution in patients with liver or renal dysfunction, as these conditions can slow down the elimination of diazepam 2.
Overall, diazepam is a highly effective medication for treating anxiety and other CNS disorders, but its use requires careful consideration of the potential risks and benefits 1.