From the Guidelines
It is not recommended to take 25mg quetiapine at the same time as a one-week course of clarithromycin without medical supervision due to potential drug interactions that may increase quetiapine levels and lead to enhanced side effects. According to the study 1, clarithromycin is a macrolide antibiotic that can substantially decrease the concentrations of certain drugs, including quetiapine, by inhibiting liver enzymes (CYP3A4) that break down these medications.
Key Considerations
- The interaction between quetiapine and clarithromycin may cause increased quetiapine levels in the bloodstream, leading to side effects such as excessive sedation, dizziness, confusion, or irregular heartbeat.
- For someone with severe mental health problems, abruptly stopping quetiapine could be harmful, but the interaction risk is also important.
- A healthcare provider may recommend temporarily reducing the quetiapine dose during the clarithromycin treatment, switching to a different antibiotic, or monitoring the patient more closely for side effects.
Recommendations
- Contact a healthcare provider immediately before continuing this combination to discuss the potential risks and benefits.
- Never adjust medication doses on your own, especially for mental health conditions where medication stability is crucial.
- Close monitoring and potential dose adjustments may be necessary to minimize the risk of adverse effects while ensuring the effectiveness of both medications.
From the FDA Drug Label
Quetiapine: Use quetiapine and clarithromycin concomitantly with caution Co-administration could result in increased quetiapine exposure and quetiapine related toxicities such as somnolence, orthostatic hypotension, altered state of consciousness, neuroleptic malignant syndrome, and QT prolongation Refer to quetiapine prescribing information for recommendations on dose reduction if co-administered with CYP3A4 inhibitors such as clarithromycin [see Drug Interactions (7)].
It is not recommended to take 25mg quetiapine at the same time as a one week course of clarithromycin without caution. Co-administration may result in increased quetiapine exposure and related toxicities. The patient should be closely monitored for signs of quetiapine toxicity, such as somnolence, orthostatic hypotension, and QT prolongation. Dose reduction of quetiapine may be necessary when co-administered with clarithromycin, a strong CYP3A4 inhibitor 2.
From the Research
Interaction between Quetiapine and Clarithromycin
- The concomitant administration of quetiapine and clarithromycin may increase the risk of adverse events, including neuroleptic malignant syndrome, as reported in a case study 3.
- A population-based retrospective cohort study found that coprescription of clarithromycin with quetiapine was associated with a higher risk of hospital encounters for encephalopathy, falls, or fractures, primarily driven by an increase in fragility fractures 4.
Dosing and Switching Strategies for Quetiapine
- The recommended titration schedule for quetiapine is 50 mg on day 1,100 mg on day 2,200 mg on day 3,300 mg on day 4, and 400 mg on day 5, administered in divided doses twice a day 5.
- Quetiapine has antipsychotic effects and good tolerability at doses ranging from 150 to 750 mg/day, and patients can be switched to quetiapine from another antipsychotic agent with careful individualization to minimize potential psychotic relapse or withdrawal symptoms 5.
Cardiovascular Risks associated with Clarithromycin
- Short-term clarithromycin administration was significantly associated with increased risk of sudden cardiovascular death in stable coronary heart disease patients not using statins 6.
Quetiapine Efficacy and Tolerability in Major Depressive Disorder
- Quetiapine XR has been shown to provide rapid and sustained symptomatic improvement in the acute and maintenance treatment of major depressive disorder, with tolerability advantages compared to duloxetine on measures of sexual dysfunction 7.