Conditions: Specific Phobia
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 20
Healthy volunteers: no

Brief summary:
The aim of the present study is to determine whether people receiving d-cycloserine and exposure therapy show different brain reactions to symptom provocation compared to people receiving placebo and exposure therapy.

Detailed description:
D-cycloserine (DCS) is a partial N-methyl-D-aspartate (NMDA) receptor agonist that may improve or accelerate extinction learning. We will randomly assign people with snake phobia to receive DCS or placebo, and then provide all participants with exposure therapy. We will examine whether people receiving DCS and vs. placebo show different brain reactions to symptom provocation before and after exposure therapy.

Arms:
arm 1: Single session (up to 3 hr) of in vivo exposure therapy plus 50 mg oral d-cycloserine administered 1 hr prior to exposure therapy session arm 2: Single session (up to 3 hr) of in vivo exposure therapy plus oral placebo capsule administered 1 hr prior to exposure therapy session

Interventions: intervention 1: D-cycloserine intervention 2: Exposure therapy intervention 3: Placebo
Intervention descriptions: intervention 1: 50 mg d-cycloserine, oral, 1 dose intervention 2: Single session graded in vivo exposure therapy, 60-180 minutes intervention 3: Single capsule of oral placebo, administered once 1 hr prior to exposure therapy

Protocol document: