Comparison of the effects of duloxetine alone versus duloxetine combined with bupropion on cognitive symptoms and depression in patients with fibromyalgia.
Design
This study is a randomized controlled clinical trial (RCT) with parallel groups that is conducted on patients with fibromyalgia referring to Imam Khomeini Clinic, Razi Hospital, Psychosomatic Clinic. The statistical population includes patients who, based on the diagnosis of the treating physician, start treatment with duloxetine (at a dose of 20 to 60 mg per day).
Patients' symptoms are assessed using the following standard tools in two stages: • Before the intervention begins (baseline). • End of the 12th week (post-intervention).
Settings and conduct
Eligible patients are randomly divided (using a random number table) by an independent researcher into two groups: 1. Intervention group: treatment with duloxetine bupropion at a dose of 150 mg per day. 2. Control group: treatment with duloxetine alone (without bupropion).
Participants/Inclusion and exclusion criteria
Adults with a confirmed diagnosis of fibromyalgia based on ACR criteria and meeting the minimum required scores on pain and depression scales.
Intervention groups
For the first group, duloxetine at a variable dosage (20 to 60 mg) plus bupropion (150 mg daily) will be prescribed; for the second group, duloxetine capsules will be prescribed at a variable dosage.
Main outcome variables
Hospital Anxiety and Depression Scale (HADS): To measure depressive symptoms. Metamemory Questionnaire (MMQ): To assess cognitive symptoms (metamemory). Visual Visual Analogue Scale (VAS): To measure pain intensity.
General information
Reason for update
Acronym
IRCT registration information
IRCT registration number:IRCT20260819070731N1
Registration date:2026-09-08, 1405/06/17
Registration timing:prospective
Last update:2026-09-08, 1405/06/17
Update count:0
Registration date
2026-09-08, 1405/06/17
Registrant information
Name
Sara Farhang
Name of organization / entity
Country
Iran (Islamic Republic of)
Phone
+98 41 3335 5921
Email address
dsfarhang@gmail.com
Recruitment status
recruiting
Funding source
Expected recruitment start date
2026-09-23, 1405/07/01
Expected recruitment end date
2027-03-20, 1405/12/29
Actual recruitment start date
empty
Actual recruitment end date
empty
Trial completion date
empty
Scientific title
Comparison of the Effects of Duloxetine Alone and in Combination with Bupropion on Cognitive Symptoms and Depression in Patients with Fibromyalgia
Public title
Duloxetine Alone and in Combination with Bupropion in Patients with Fibromyalgia
Purpose
Treatment
Inclusion/Exclusion criteria
Inclusion criteria:
Age between 18 and 65 years
Definitive diagnosis of fibromyalgia based on ACR criteria
Meeting the minimum required scores on pain and depression scales (to ensure the presence of assessable symptoms)
o changes to other pharmacological or non-pharmacological treatments over the past 3 months
Written informed consent to participate in the study
Exclusion criteria:
Presence of major comorbid psychiatric disorders (e.g., psychosis, bipolar disorder, substance abuse)
Presence of comorbid physical conditions that could explain cognitive symptoms or pain (e.g., uncontrolled hypothyroidism, multiple sclerosis)
Hypersensitivity to duloxetine or bupropion
Pregnancy or breastfeeding
Presence of unstable medical conditions likely requiring immediate intervention
Pain symptoms associated with conditions other than fibromyalgia that might interfere with the interpretation of results
Current or past confirmed diagnosis of rheumatoid arthritis, inflammatory arthritis, or other autoimmune diseases
Severe liver disease
History of using medications that affect cognition (e.g., acetylcholinesterase inhibitors and anticonvulsants)
Patient intolerance to the prescribed medication or development of adverse effects (bupropion or duloxetine)
Age
From 18 years old to 65 years old
Gender
Both
Phase
3
Groups that have been masked
Participant
Care provider
Investigator
Outcome assessor
Data analyser
Sample size
Target sample size:
40
Randomization (investigator's opinion)
Randomized
Randomization description
Using a random number table
In this method, each participant in the study is assigned a number (from 1 to 40; depending on the sample size) and a subset of the population is randomly selected using a random number table. Even numbers are assigned to the duloxetine alone group and odd numbers are assigned to the duloxetine plus bupropion group.
Blinding (investigator's opinion)
Double blinded
Blinding description
The study will be conducted in a double-blind manner. Following randomization, bupropion and placebo capsules, which will be identical in appearance, color, packaging, and administration schedule, will be provided to participants in sealed and coded packages for concomitant use with duloxetine. The allocation codes will be maintained by an individual who is independent of the assessment and data collection processes. Neither the participants nor the researcher responsible for clinical assessments and data collection will be aware of the treatment allocation. In addition, the data analyst will remain blinded to the allocation codes until completion of the statistical analysis and finalization of the results.
Placebo
Not used
Assignment
Parallel
Other design features
Secondary Ids
empty
Ethics committees
1
Ethics committee
Name of ethics committee
دانشگاه علوم پزشکی تبریز (کمیته اخلاق در پژوهش)
Street address
Golgasht
City
Tabriz
Province
East Azarbaijan
Postal code
5166614766
Approval date
2026-06-08, 1405/03/18
Ethics committee reference number
IR.TBZMED.REC.1405.163
Health conditions studied
1
Description of health condition studied
Fibromyalgia
ICD-10 code
M79.7
ICD-10 code description
Fibromyalgia
Primary outcomes
1
Description
Hospital Anxiety and Depression Scale
Timepoint
Before the start of the intervention and at the end of the twelfth week
Method of measurement
HADS questionnaire
2
Description
Memory test
Timepoint
Before the start of the intervention and at the end of the twelfth week
Method of measurement
MMQ
3
Description
Pain
Timepoint
Before the start of the intervention and at the end of the twelfth week
Method of measurement
VAS
Secondary outcomes
empty
Intervention groups
1
Description
Intervention group: Treatment with duloxetine (with a dose of 20 to 60 mg per day) + bupropion at a dose of 150 mg per day
Category
Treatment - Drugs
2
Description
Control group: Treatment with duloxetine alone (with a dose of 20 to 60 mg per day)
Category
Treatment - Drugs
Recruitment centers
1
Recruitment center
Name of recruitment center
کلینیک امام خمینی
Full name of responsible person
دکتر سارا فرهنگ
Street address
Golgasht
City
Tabriz
Province
East Azarbaijan
Postal code
5166614766
Phone
+98 41 3335 9680
Email
dsfarhang@gmail.com
Sponsors / Funding sources
1
Sponsor
Name of organization / entity
Tabriz University of Medical Sciences
Full name of responsible person
دکتر خسرو ادیبکیا
Street address
Golgasht st.
City
Tabriz
Province
East Azarbaijan
Postal code
5166614766
Phone
+98 41 3335 5921
Email
dsfarhang@gmail.com
Grant name
Grant code / Reference number
Is the source of funding the same sponsor organization/entity?
Yes
Title of funding source
Tabriz University of Medical Sciences
Proportion provided by this source
100
Public or private sector
Public
Domestic or foreign origin
Domestic
Category of foreign source of funding
empty
Country of origin
Type of organization providing the funding
Academic
Person responsible for general inquiries
Contact
Name of organization / entity
Tabriz University of Medical Sciences
Full name of responsible person
Sara Farhang
Position
Professor
Latest degree
Specialist
Other areas of specialty/work
Psychiatrics
Street address
Golgasht
City
Tabriz
Province
East Azarbaijan
Postal code
5166614766
Phone
+98 41 3335 5921
Fax
Email
dsfarhang@gmail.com
Person responsible for scientific inquiries
Contact
Name of organization / entity
Tabriz University of Medical Sciences
Full name of responsible person
Sara Farhang
Position
Professor
Latest degree
Specialist
Other areas of specialty/work
Psychiatrics
Street address
Golgasht
City
Tabriz
Province
East Azarbaijan
Postal code
5166614766
Phone
+98 41 3335 5921
Fax
Email
dsfarhang@gmail.com
Person responsible for updating data
Contact
Name of organization / entity
Tabriz University of Medical Sciences
Full name of responsible person
Sara Farhang
Position
Professor
Latest degree
Specialist
Other areas of specialty/work
Psychiatrics
Street address
Golgasht
City
Tabriz
Province
East Azarbaijan
Postal code
5166614766
Phone
+98 41 3335 5921
Fax
Email
dsfarhang@gmail.com
Sharing plan
Deidentified Individual Participant Data Set (IPD)
Undecided - It is not yet known if there will be a plan to make this available
Study Protocol
No - There is not a plan to make this available
Statistical Analysis Plan
No - There is not a plan to make this available
Informed Consent Form
Yes - There is a plan to make this available
Clinical Study Report
Yes - There is a plan to make this available
Analytic Code
Not applicable
Data Dictionary
Not applicable
Title and more details about the data/document
Information on the main outcomes will be reported.
When the data will become available and for how long
6 months after the results are published
To whom data/document is available
Researchers working in academic and scientific institutions
Under which criteria data/document could be used
The data will be available for use in other studies such as review studies.
From where data/document is obtainable
Dr. Sara Farhang, Associate Professor of Psychiatry, Razi Psychiatric University Hospital, El Goli Boulevard, POB 5456
Tabriz, I.R.IRAN.
dsfarhang@gmail.com
Fax:+98+413+3803353.
What processes are involved for a request to access data/document
Email to correspondence
Dr. Sara Farhang, Associate Professor of Psychiatry, Razi Psychiatric University Hospital, El Goli Boulevard, POB 5456
Tabriz, I.R.IRAN.
dsfarhang@gmail.com
Fax:+98+413+3803353.