Drug interactions
Efavirenz + Protriptyline
Severity: Moderate
Efavirenz and Protriptyline: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Efavirenz and tricyclic antidepressants can both prolong the QT interval, so combining them may increase the risk of arrhythmia. Efavirenz may also alter tricyclic levels through CYP effects, and CNS adverse effects can overlap.
What this interaction means in plain words
Efavirenz and Protriptyline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Additive QT prolongation, with possible CYP-mediated changes in tricyclic exposure.
What to do
Obtain a baseline ECG and monitor it, correcting electrolyte disturbances. Monitor for anticholinergic and CNS effects and consider an alternative antidepressant if QT risk is high.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Efavirenz
- Cobimetinib + Efavirenz Contraindicated
- Dienogest / estradiol valerate + Efavirenz Contraindicated
- Dihydroergotamine intranasal + Efavirenz Contraindicated
- Dihydroergotamine + Efavirenz Contraindicated
- Doravirine + Efavirenz Contraindicated
- Efavirenz + Elbasvir / grazoprevir Contraindicated
Frequently asked questions
Can I take Efavirenz with Protriptyline?
MediHelp rates the interaction as moderate. Efavirenz and Protriptyline can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Efavirenz and tricyclic antidepressants can both prolong the QT interval, so combining them may increase the risk of arrhythmia. Efavirenz may also alter tricyclic levels through CYP effects, and CNS adverse effects can overlap.
How serious is the interaction between Efavirenz and Protriptyline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain a baseline ECG and monitor it, correcting electrolyte disturbances. Monitor for anticholinergic and CNS effects and consider an alternative antidepressant if QT risk is high.
What other medicines interact with Efavirenz?
MediHelp also lists interactions of Efavirenz with, for example, Cobimetinib, Dienogest / estradiol valerate, Dihydroergotamine intranasal. The full list is on the Efavirenz page.
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