Oral benzodiazepines for anxiolysis (minimal sedation) in dentistry

Low-dose oral benzodiazepines can be given preprocedurally to reduce anxiety before and during dental treatment. Their advantages and disadvantages are shown in Advantages and disadvantages of oral benzodiazepines and inhaled nitrous oxide for anxiolysis in dentistry. Adverse effects are described below.

Do not use benzodiazepines for anxiolysis in children or adolescents outside the specialist setting. In adults, carefully consider the appropriateness of benzodiazepines for anxiolysis (minimal sedation)—see Patient groups at increased risk of adverse outcomes with anxiolysis (minimal sedation) for a list of patients at increased risk of adverse outcomes. When determining the appropriateness of benzodiazepine use, consider the patient’s previous sedative use, medication history, alcohol intake and illicit drug use because sedation is increased by concomitant administration of sedative drugs. Also consider the legislation about prescribing drugs of dependence.

Note: Do not use benzodiazepines for anxiolysis in children and adolescents outside the specialist setting.

The factors that influence the appropriateness of benzodiazepine use also influence the required dose; sedative-naive patients usually respond to a low dose and are more sensitive to the adverse effects of benzodiazepines, whereas patients who have a tolerance to sedating drugs (eg hypnotics, opioids, alcohol, cannabis) may require higher doses—seek expert advice. The response to oral benzodiazepines is widely variable. Use the lowest dose possible and do not use more than one benzodiazepine concurrently.

Note: Use the lowest dose of benzodiazepine possible and do not use more than one benzodiazepine concurrently.

Most benzodiazepines are considered equally effective at equivalent doses; differences are explained by their pharmacokinetic properties (see Pharmacokinetic properties of benzodiazepines used in dentistry). Benzodiazepines, particularly those with a longer duration of action (eg diazepam) may cause prolonged drowsiness, which can persist the day after administration. Benzodiazepines with a shorter duration of action are preferred; however, midazolam and alprazolam are not recommended for dental procedures.

Table 1. Pharmacokinetic properties of benzodiazepines used in dentistry
Drug	Time to peak plasma concentration after oral administration [NB1]	Elimination half-life
diazepam	30 to 90 minutes	1 to 5 days [NB2]
lorazepam	120 minutes	10 to 20 hours
oxazepam	120 to 180 minutes	4 to 15 hours
temazepam	30 to 120 minutes	8 to 15 hours
Note: NB1: Benzodiazepines are generally fully absorbed after oral administration. NB2: Diazepam has an elimination half-life of 1 to 2 days; its active metabolite has an elimination half-life of 2 to 5 days.

For adults not at increased risk of adverse outcomes, typical regimens for anxiolysis (minimal sedation) using short-acting benzodiazepines are:

1 lorazepam 1 mg orally, 1 to 2 hours before the procedure, administered at the dental practice anxiolysis, dental procedures lorazepam

1 oxazepam 7.5 mg orally, 1 to 2 hours before the procedure, administered at the dental practice anxiolysis, dental procedures oxazepam

1 temazepam 10 mg orally, 1 hour before the procedure, administered at the dental practice. anxiolysis, dental procedures temazepam

If a longer duration of anxiolysis is required for adults not at increased risk of adverse outcomes, use:

diazepam 5 mg orally, 1 hour before the procedure, administered at the dental practice. anxiolysis, dental procedures diazepam

For adults at increased risk of adverse outcomes, consider using a lower dose or reconsider the appropriateness of administering benzodiazepines for anxiolysis.

Adverse effects of benzodiazepines include impaired psychomotor performance, impaired memory function, delirium, dry mouth and blurred vision. Elderly or frail patients are particularly susceptible to ataxia (with consequent falls and injury), confusion, memory dysfunction (both retrograde and anterograde amnesia) and cognitive impairment.

Warn patients that the adverse effects of benzodiazepines can affect their behaviour, coordination and ability to drive or operate machinery safely.

All benzodiazepines can produce discontinuation symptoms; these can be physiological or psychological, and are related to the dose and duration of use. Rebound anxiety can occur after a single dose of a short-acting benzodiazepine, particularly alprazolam or midazolam. Because of the potential for tolerance and dependence with continued use, only a single dose of benzodiazepine should be prescribed.