Pharmacologic management of dental anxiety: conscious versus unconscious sedation

Early onset anxiolytic efficacy after a single dose of pregabalin: double-blind, placebo- and active-comparator controlled evaluation using a dental anxiety model

To evaluate acute onset of anxiolytic activity using a dental anxiety model, 89 patients were randomised to double-blind single dose pregabalin 150 mg, alprazolam 0.5 mg or placebo 4 h before a scheduled dental procedure. A Dental Anxiety Total score >12 (moderate-to-severe) without meeting Diagnostic and Statistical Manual of Mental Disorders (Fourth edition) (DSM-IV) anxiety disorder criteria was required. Efficacy and safety, assessed 2, 2.5, 3, 3.5 and 4 h postdose, included 100 mm Visual Analogue Scale for Anxiety (VAS-Anxiety; primary outcome), 100 mm VAS-Sedation and Time-to-Onset of Action Scale (TOAS), a patient-rated anti-anxiety drug-benefit scale (no [0] to full benefit [10]). Mixed model analysis found significantly greater VAS-A improvement slopes for pregabalin (t = -2.47; P = 0.014) and alprazolam (t = -2.39; P = 0.018). There was a significant improvement versus placebo in the TOAS from 2 h through endpoint in alprazolam patients and from 3 h onward in pregabalin patients. Pregabalin produced significantly greater increases in VAS-Sedation versus placebo from 2.5 h through 4 h (2 h onward for alprazolam). Notably, there was a higher correlation between TOAS and VAS-Sedation (r = +0.58) than VAS-Anxiety (r = -0.50) on Spearman's analysis. The majority of Adverse Effects (AEs) were mild, and the most frequent for pregabalin, alprazolam, and placebo, respectively, were fatigue (N = 7, 7, 3), dizziness (N = 6, 3, 3), attention disturbance (N = 3, 1, 0), somnolence (N = 3, 0, 0), feeling abnormal (N = 0, 2, 0) and balance disorder (N = 0, 2, 0). These results suggest that onset of clinically meaningful anxiolytic effect after single-dose pregabalin occurs within the first 3-4 h. Additional research is needed to determine whether anxiolytic effect occurs in generalized anxiety disorder populations by day 1 or within 3-4 h post-first dose.

Expanded studies of the pharmacokinetics and clinical effects of multidose sublingual triazolam in healthy volunteers

Previous work described the pharmacokinetics and clinical effects of multidose sublingual triazolam (Halcion; Pharmacia & Upjohn Co, Kalamazoo, Mich). This laboratory study evaluated the hypothesis that incremental dosing of triazolam produces dose-dependent central nervous system depression that is profound and long lasting. Forty-nine healthy adults between the ages of 21 and 39 years, not receiving dental treatment, were randomly assigned to placebo (n = 12) or 1 of 3 triazolam groups (0.25-mg single dose, n = 12; 0.5 mg divided between 2 equal doses for 60 minutes, n = 12; or 0.75 mg divided among 3 doses for 90 minutes, n = 13). Plasma triazolam concentrations were determined. Bispectral index (BIS) and the Observer Assessment of Alertness/Sedation scale were used to assess sedation. Plasma triazolam concentrations increased with time in all subjects, with Tmax and Cmax both increasing dose dependently. Compared with placebo, all dosing paradigms produced dose-dependent BIS suppression and sedation. The single dose of 0.25 mg reached its peak BIS suppression at 90 (81 +/- 7) minutes and sedation at 120 (3.6 +/- 0.5) minutes and returned to baseline before 360 minutes. In contrast, incremental dosing of 0.5 and 0.75 mg produced profound and long-lasting BIS suppression and sedation that did not plateau until either 180 or 210 minutes as measured by the BIS index (67 +/- 14 and 60 +/- 16 at 0.5 and 0.75 mg, respectively) and 150 minutes as measured by the Observer Assessment of Alertness/Sedation scale (3.2 +/- 1.0 and 2.7 +/- 0.4 at 0.5 and 0.75 mg, respectively). These data more fully characterize the effects of incremental dosing with sublingual triazolam and provide additional insight for discharge safety recommendations.