From the Guidelines
Duloxetine is associated with akathisia, a side effect characterized by restlessness, in some patients, as reported in the most recent study 1. The association between duloxetine and akathisia is not explicitly mentioned in the provided studies, but the study from 2020 1 lists various adverse effects of SNRIs, including duloxetine, such as agitation and behavioral activation, which can be related to restlessness. However, the most recent and highest quality study 1 does not specifically mention akathisia as a side effect of duloxetine, but it does discuss the importance of managing adverse events, which may include restlessness, in patients taking duloxetine for neuropathic pain. Some key points to consider when managing restlessness or akathisia in patients taking duloxetine include:
- Reducing the dose or changing the timing of the dose
- Switching to a different antidepressant
- Prescribing a beta-blocker or benzodiazepine for short-term relief
- Maintaining regular exercise, practicing relaxation techniques, and avoiding caffeine to manage the side effect. It is essential to consult a healthcare provider if restlessness or akathisia occurs while taking duloxetine, as they can recommend the best course of action to manage the side effect while continuing treatment.
From the FDA Drug Label
Adverse Reactions in the DPNP, FM, OA, and CLBP Adult Trials Table 4 displays the incidence of adverse reactions that occurred in 2% or more of duloxetine delayed-release capsules-treated patients (determined prior to rounding) in the premarketing acute phase of DPNP, FM, OA, and CLBP placebo-controlled adult trials and with an incidence greater than placebo-treated patients ... Psychiatric Disorders Insomnia b,h Agitation i 10 3 ... h Includes feeling jittery, nervousness, restlessness, tension and psychomotor hyperactivity.
Duloxetine is associated with restlessness, as indicated by the term "restlessness" included in the definition of agitation (i) in the adverse reactions table for DPNP, FM, OA, and CLBP adult trials 2. Additionally, the postmarketing experience section of another label also mentions "restless legs syndrome" as an adverse reaction reported since market introduction that was temporally related to duloxetine therapy 2.
From the Research
Association of Duloxetine with Akathisia
- There is no direct evidence in the provided studies that specifically links duloxetine to akathisia (restlessness) 3, 4, 5, 6, 7.
- However, studies have reported various side effects associated with duloxetine, including nausea, dry mouth, headache, constipation, dizziness, and fatigue 3, 4.
- One study reported that duloxetine may cause panic attacks in some patients, which could be related to restlessness or anxiety 6.
- Another study found that discontinuation of duloxetine can lead to symptoms such as dizziness, nausea, headache, and irritability, which may be related to akathisia 7.
- It is essential to note that the provided studies do not explicitly mention akathisia as a side effect of duloxetine, but they do report other related symptoms 3, 4, 5, 6, 7.
Side Effects of Duloxetine
- Common side effects of duloxetine include nausea, headache, dry mouth, dizziness, and fatigue 3, 4.
- Duloxetine can also cause discontinuation-emergent adverse events, such as dizziness, nausea, headache, and irritability, when treatment is stopped abruptly 7.
- The study on duloxetine-related panic attacks suggests that duloxetine can cause anxiety and panic attacks in some patients 6.
Pharmacokinetics and Drug Interactions
- Duloxetine is a potent reuptake inhibitor of serotonin and norepinephrine, with a maximum plasma concentration of approximately 47-110 ng/mL 5.
- The elimination half-life of duloxetine is approximately 10-12 hours, and the volume of distribution is approximately 1640 L 5.
- Duloxetine can interact with other drugs, such as CYP1A2 inhibitors, which can increase duloxetine exposure 5.