Overview
Fibromyalgia (FM) is a chronic pain syndrome characterized by widespread pain, fatigue, and emotional disorders. Its onset is related to factors such as central sensitization and imbalance of neurotransmitters. The current mainstream treatments include pregabalin, but the efficacy of pregabalin is limited, with only 25%-40% pain relief rate, and adverse reactions are common. Selective serotonin and norepinephrine reuptake inhibitors (SNRIs), such as duloxetine and venlafaxine, have demonstrated efficacy in FM by modulating pain pathways through increased serotonin and norepinephrine availability. Desvenlafaxine, the third SNRI, was found with lower adverse effects compared with duloxetine and venlafaxine. We hypothesize that the combination of pregabalin with desvenlafaxine may offer greater pain relief compared pregabalin monotherapy, without a significant increase in adverse effects for patients with FM.
Eligibility
Inclusion Criteria:
- Diagnosed with FM according to the 2016 Revisions to the 2010/2011 FM diagnostic criteria;
- Aged 18 years or older;
- Experiencing moderate to severe FM that have not been effectively alleviated by non-pharmacological treatments and has not received currently recommended pharmacological treatment for FM;
- Numeric rating scale (NRS) score ≥ 4 at baseline;
- Aspartate aminotransferase and alanine aminotransferase levels less than twice the upper limit of normal;
- Estimated glomerular filtration rate of 30 mL/min per 1.73 m2 or higher;
- Willing to sign the informed consent form and possessing sufficient cognitive and language abilities to comply with all the study requirements.
Exclusion criteria
- History of hypersensitivity to pregabalin, desvenlafaxine or any of its excipients;
- History of epilepsy, or depression requiring antidepressant medications;
- Pregnancy or breastfeeding;
- Presence of serious systemic diseases, including uncontrolled hypertension, uncontrolled diabetes, or significant cardiac dysfunction;
- With acute or chronic pain conditions other than FM.