Antibiotic boosts therapy for social anxiety – timing matters
NCT ID NCT02066792
First seen Jun 27, 2026 · Last updated Jun 27, 2026
Summary
This study tested whether D-cycloserine, an antibiotic that helps the brain unlearn fear, can improve cognitive-behavioral therapy (CBT) for social anxiety. 152 adults with social anxiety took either D-cycloserine or a placebo before or after their therapy sessions. Researchers wanted to see if the drug, especially when taken after a successful session, could reduce anxiety symptoms more than therapy alone.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- D-cycloserine (an antibiotic also used to enhance fear extinction learning)
- What this could lead to
- If it works, this could make cognitive-behavioral therapy more effective for people with social anxiety, leading to faster or longer-lasting symptom relief.
- What could go wrong
- This is an early-phase trial with a small sample, so results may not be conclusive. The effect of D-cycloserine may depend on timing and therapy success, and it may not work for everyone.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
-
Early phase 1
The earliest testing in people: a first look at safety, in a very small group.
- Participants
-
152 people
The number who actually took part.
- Started
-
Apr 2014
- Finished
-
Jul 2018
- Lead sponsor
-
Other sponsor
The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
-
18 to 70 years
- Sex
-
Anyone
- Healthy volunteers
-
Accepted
You do not need to have the condition being studied to take part.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
Inclusion Criteria: * Male or female outpatients \> 18 years of age with a primary psychiatric diagnosis (designated by the patient as the most important source of current distress) of social anxiety disorder as defined by DSM-5 criteria. * A total score \> 60 on the LSAS. * Physical examination and laboratory findings without clinically significant abnormalities. * Willingness and ability to participate in the informed consent process and comply with the requirements of the study protocol. Exclusion Criteria: * A lifetime history of bipolar disorder, schizophrenia, psychosis, delusional disorders or obsessive-compulsive disorder; an eating disorder in the past 6 months; organic brain syndrome, mental retardation or other cognitive dysfunction that could interfere with capacity to engage in therapy; a history of substance or alcohol abuse or dependence (other than nicotine) in the last 6 months or otherwise unable to commit to refraining from alcohol use during the acute period of study participation. * PTSD within the past 6 months. Entry of patients with other mood or anxiety disorders will be permitted if the SAD is judged to be the predominant disorder, in order to increase accrual of a clinically relevant sample. Patients with significant suicidal ideation (MADRS item 10 score \> 3) or who have enacted suicidal behaviors within 6 months prior to intake will be excluded from study participation and referred for appropriate clinical intervention. * Patients must be off concurrent psychotropic medication (e.g., antidepressants, anxiolytics, beta blockers) for at least 2 weeks prior to initiation of randomized treatment. * Significant personality dysfunction likely to interfere with study participation. * Serious medical illness or instability for which hospitalization may be likely within the next year. * Patients with a current or past history of seizures. * Pregnant women, lactating women, and women of childbearing potential who are not using medically accepted forms of contraception (e.g., IUD, oral contraceptives, barrier devices, condoms and foam, or implanted progesterone rods stabilized for at least 3 months). * Any concurrent psychotherapy initiated within 3 months of baseline, or ongoing psychotherapy of any duration directed specifically toward treatment of the SAD is excluded. Prohibited psychotherapy includes CBT or psychodynamic therapy focusing on exploring specific, dynamic causes of the phobic symptomatology and providing management skills. General supportive therapy initiated \> 3 months prior is acceptable. * Prior non-response to adequately-delivered exposure (i.e., as defined by the patient's report of receiving specific and regular exposure assignments as part of a previous treatment). * Patients with a history of head trauma causing loss of consciousness, seizure or ongoing cognitive impairment. Current use of isoniazid or ethionamide compounds * Insufficient command of the English language
Get updates
Get notified about this study
Sign up to get updates when this study changes or when new studies for Social anxiety disorder are added.
Genom att skicka in godkänner du våra Användarvillkor
Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
-
Boston University
Boston, Massachusetts, 02215, United States
-
Rush University Medical Center
Chicago, Illinois, 60612, United States
-
University of Texas at Austin
Austin, Texas, 78712, United States
More trials for these conditions
Other studies related to the condition(s) this trial covers.
- Can a computer game rewire anxious Kids' brains?
- Can tailored brain stimulation quiet anxiety that drugs Can't?
- Can meditation rewire the anxious social brain?
- One-Size-Fits-All anxiety therapy may be a thing of the past
- Ear-Zapping device may tame social anxiety — trial puts it to the test
- Can an AI coach help therapists treat depression and anxiety online?