Using acetazolamide to treat treatment-resistant schizophrenia

A Randomized Controlled Trial of Acetazolamide for Patients With Treatment Resistant Schizophrenia

Phase1; Phase2 Interventional University of Pittsburgh · NCT04887792

This study is testing if adding acetazolamide to the treatment of adults with schizophrenia who haven't responded well to regular medications can help improve their symptoms.

Quick facts

PhasePhase1; Phase2
Study typeInterventional
Enrollment60 (estimated)
Ages18 Years to 55 Years
SexAll
SponsorUniversity of Pittsburgh Academic / other
Locations2 sites (Pittsburgh, Pennsylvania and 1 other locations)
Trial IDNCT04887792 on ClinicalTrials.gov

What this trial studies

This is a double-blind, randomized controlled trial investigating the efficacy of acetazolamide as an adjunctive treatment for individuals with treatment-resistant schizophrenia. The study aims to enroll patients aged 18-55 who have shown inadequate response to standard antipsychotic medications. Participants will receive either acetazolamide or a placebo while continuing their stable dose of antipsychotic drugs. The trial seeks to evaluate improvements in both positive and negative symptoms of schizophrenia, leveraging previous findings that indicated acetazolamide may enhance treatment outcomes.

Who should consider this trial

Good fit: Ideal candidates for this study are adults aged 18-55 with treatment-resistant schizophrenia, characterized by a PANSS total score greater than 60.

Not a fit: Patients with a history of substance abuse, certain medical conditions, or contraindications to acetazolamide will not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new option for patients with schizophrenia who do not respond adequately to existing antipsychotic medications.

How similar studies have performed: Previous studies have shown promising results with acetazolamide in improving symptoms of schizophrenia, indicating potential for success in this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Written informed consent.
* Both genders, ages 18-55 years (older patients may not tolerate high ACZ dose).
* PANSS total score \> 60 and Score \> 4 on one or more items of the 'positive' syndrome items (P1-P7), following treatment at therapeutic doses for 6 weeks with different APDs on 2 occasions.
* Stable dose of antipsychotic drug (APD) for \> 1 month, continued throughout the study.
* Not participating in another randomized controlled clinical trial (RCT).

Exclusion Criteria:

* Substance abuse in the past month/dependence past 6 months with the exception of methadone prescribed for opiate withdrawal.
* History or current medical/neurological illnesses that may lead to unstable course, e.g., epilepsy.
* Pregnancy.
* Acetazolamide (ACZ) contraindications: hypersensitivity to ACZ; history of renal hyperchloremic acidosis; Addison's disease/adrenal failure; chronic closed angle-closure glaucoma.
* Current or prior treatment with ACZ or history of hypersensitivity to ACZ.
* Intellectual disability as defined in DSM 5.

Where this trial is running

Pittsburgh, Pennsylvania and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions SchizophreniaSchizo Affective Disorderacetazolamide
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.