Condition category
Nervous System Diseases
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
Antipsychotic medications (‘antipsychotics’) are used to treat people with symptoms of psychosis which usually occur in schizophrenia or bipolar depression. People with psychosis may hear voices or see things that aren’t real. Antipsychotics affect the number of chemicals in the brain to help stabilise how people feel and reduce the symptoms of psychosis. Unfortunately, antipsychotics can have side effects such as stiffness and shakiness of the body. This is because they treat an area of the brain that is also involved in the control of muscle movement. Tardive dyskinesia (TD) is the name used to describe the involuntary sudden muscle movements of the face and/or body which can occur when people take antipsychotics. TD muscle movements and facial twitches can sometimes be painful and make sufferers feel very self-conscious. TD symptoms can disappear when a person stops their medication, but this isn’t always the case. Also, some people are not able to stop their medication and must find ways to manage the symptoms of TD. There are some treatments that can be taken alongside antipsychotics to help control TD, including tranquiliser medicines or health supplements. Vitamin E is one such health supplement that has been shown to help TD symptoms. Cannabidiol (CBD), a compound found in cannabis, is being tested as a potential treatment for TD which can be taken alongside antipsychotics. CBD doesn’t make people feel ‘stoned’, but it can control symptoms such as pain, muscle spasms and inflammation which are experienced in a variety of diseases and disorders. CBD usually comes in tablet form. The aim of this study is to compare how well CBD works on managing symptoms of TD compared with vitamin E when taken alongside antipsychotics.

Who can participate?
Adults taking antipsychotic medication for a psychotic disorder.

What does the study involve?
Participants are randomly allocated into one of two groups. Those in group 1 (intervention group) take CBD tablets twice a day for 6 weeks. Those in group 2 (control group) take vitamin E tablets daily for 6 weeks. Participants complete questionnaires and attend assessments at the start of the study, then 2 weeks, 4 weeks and 6 weeks during treatment, then at 12 weeks follow-up. Routine blood tests are carried out before the start of the trial.

What are the possible benefits and risks of participating?
The results of this study may benefit future patients if an improvement in the symptoms of TD is found. There are no significant adverse drug reactions to cannabidiol, but some mild and transient side effects include headache, dizziness and nausea.

Where is the study run from?
Federal Neuropsychiatric Hospital (Nigeria)

When is the study starting and how long is it expected to run for?
December 2015 to September 2019

Who is funding the study?
Federal Neuropsychiatric Hospital (Nigeria)

Who is the main contact?
Dr J Kajero

Trial website

Contact information



Primary contact

Dr Jaiyeola Kajero


Contact details

8 Harvey Road Yaba Lagos
+234 08037140976

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Investigation of the potential beneficial effects of cannabidiol in the management of oral-lingual-buccal dyskinesias using animal studies and a clinical trial


Study hypothesis

1. Hypothesis: there are significant differences and better outcomes for patients on cannabidiol in the management of oral-lingual-buccal dyskinesia.
1.1. Null hypothesis: there are no differences between cannabidiol and vitamin E in the management of anti-psychotic induced oral-lingual-buccal dyskinesia.
2. Hypothesis: there is no difference or minimal difference in the side effect profile of cannabidiol and vitamin E when used in the management of antipsychotic induced oral-lingual-buccal dyskinesia.
2.1. Null hypothesis: patients on cannabidiol have more side effects than patients on vitamin E in the management of antipsychotic induced oral-lingual-buccal dyskinesia.

Ethics approval

Ethics committee Nigerian Institute of Medical Research, 26/11/2014, ref: IRB/14/271

Study design

Proof of concept, double blind placebo controlled study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use contact details to request a participant information sheet.


Tardive dyskinesia


1. Group 1 has high cannabidiol extract Nabidiolex® (CBD) (300mg) administered twice a day for six weeks as an adjunctive treatment alongside their usual antipsychotic medication. CBD will be administered orally in capsules.
2. Group 2 has vitamin E (400IU) administered daily for six weeks as an adjunctive treatment alongside their usual antipsychotic medication

Intervention type



Drug names

Primary outcome measure

Improvement in symptoms of tardive dyskinesia measured using the Abnormal Involuntary Movement Scale (AIMS). Assessments will be conducted at baseline, 2 weeks, 4 weeks, 6 weeks (post-treatment) and at 12 weeks follow-up.

Secondary outcome measures

1. Side effects of CBD will be periodically assessed with the Glasgow check list and reported at each assessment
2. Improvement in psychotic symptoms

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Adults 18 years and older
2. Currently meets the ICD-10 diagnosis of a psychotic disorder, verified with the Mini International Neuropsychiatric Interview (MINI-PLUS) questionnaire.
3. Currently meets the clinical diagnosis of tardive dyskinesia confirmed with the Abnormal Involuntary Movement Scale (AIMS)
4. Patients should currently be receiving treatment for a psychotic disorder and should be on either the atypical or conventional antipsychotics
5. Patient gives informed consent

Participant type


Age group




Target number of participants

28 per group

Participant exclusion criteria

1. ICD-10 diagnosis of an organic mental illness, substance misuse disorder or a seizure disorder
2. Serious or chronic physical illness
3. Known severe drug allergies or hypersensitivity to CBD

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Federal Neuropsychiatric Hospital

Sponsor information


Stellenbosch University

Sponsor details

South Africa Research Chair in PTSD
Department of Psychiatry
South Africa
+27 21 808 9111

Sponsor type




Funder type

Hospital/treatment centre

Funder name

Federal Neuropsychiatric Hospital (Nigeria)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

The work is part of a PhD thesis being submitted to the Stellenbosch University South Africa and can only be published after the completion of the whole thesis, following approval from the University. Tentatively, this would be towards early 2020.

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

13/12/2017: The recruitment end date was changed from 01/06/2016 to 31/03/2019. The overall trial end date was changed from 01/12/2016 to 30/09/2019. The intention to publish date was changed from 01/01/2018 to 31/01/2020.