Amitriptyline and Telavancin: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Amitriptyline
Telavancin
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
You've been prescribed amitriptyline (a medicine often used for mood, nerve pain, or sleep) and telavancin (an antibiotic given by IV). Both of these can affect the timing of your heartbeat, something doctors call QT prolongation. When two medicines that do this are used together, the effect can add up and, rarely, lead to an irregular heartbeat.
Please don't worry or stop either medicine on your own. This is a known combination that your care team can handle safely, usually by keeping a closer eye on your heart while you're on both. If you feel your heart racing, skipping, dizziness, or faint, let someone know right away.
Effect: Additive risk of QT interval prolongation when amitriptyline (a TCA with known QT liability) is combined with telavancin (QT prolongation observed in clinical trials).
- Mechanism: Pharmacodynamic (additive), not a CYP/transporter-based PK interaction. Neither agent is a prodrug here.
- Direction: Increased combined QT-prolonging effect.
- Onset: Unspecified.
- Evidence: Theoretical, but severity rated major given torsades potential.
Management: Use with caution. If concomitant therapy is required, obtain baseline and follow-up ECGs, monitor electrolytes (K+, Mg2+), correct deficiencies, and review other QT-prolonging agents. Consider an alternative antibiotic or antidepressant where feasible.
What happens
An increased risk of QT interval prolongation
Interaction Deep Dive
During clinical trials, telavancin was found to lengthen the QT interval. For this reason, caution should be exercised when telavancin is given together with other agents capable of prolonging the QT interval1, amitriptyline among them. Should combined treatment be necessary, monitor closely for prolongation of the QT interval.
Why it happens (mechanism)
Additive effects on QT interval prolongation
How to manage this interaction
This combination is manageable, and your care team has clear ways to keep you safe:
- Keep taking both medicines as prescribed unless your doctor or pharmacist tells you otherwise.
- Your team may check an ECG (heart tracing) and monitor you more closely while you're on both drugs.
- They may also check blood levels like potassium and magnesium, since low levels can add to the risk.
- Sometimes the team may choose a different antibiotic or adjust therapy, individualized to you.
Tell your pharmacist or doctor about any other medicines you take, and report palpitations, dizziness, or fainting promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) Across 3 clinical trials, QTc prolongation exceeding 60 msec occurred in 1.5% (15 of 2062) of patients given telavancin 10 mg/kg versus 0.6% (6 of 2062) of patients given vancomycin. Within these studies, 21% (214 of 1029) of telavancin-treated patients and 16% (164 of 1033) of vancomycin-treated patients were taking concurrent medications recognized to prolong QTc. Among those who had QTc prolongation greater than 60 msec, 9 telavancin-treated patients and 1 vancomycin-treated patient were receiving concomitant medications known to prolong the QTc interval, while fewer than 1% in each group were not receiving such a concomitant medication. An additional analysis found that 1 telavancin-treated patient and 2 vancomycin-treated patients had a QTc exceeding 500 msec. No patient had a cardiac adverse event attributed to QTc prolongation 1.
b) In a randomized, double-blind, multiple-dose, positive- and placebo-controlled, parallel study, the maximum QTc prolongation reached 11.6 msec (upper 90% confidence limit (CL), 16 msec) and 15.1 msec (upper 90% CL, 20 msec) in patients receiving telavancin 7.5 mg/kg and 15 mg/kg, respectively, versus 21.6 msec (upper 90% CL 26 msec) in the positive-control group. Healthy subjects (n=160) were assigned at random to telavancin 7.5 mg/kg, telavancin 15 mg/kg, positive control, or placebo, each infused over 60 minutes once daily for 3 days. At the conclusion of the infusion, the mean maximum baseline-corrected, placebo-corrected estimate of QTc prolongation for telavancin 10 mg/kg (derived by interpolating the data from patients given telavancin 7.5 mg/kg and 15 mg/kg) was 12 to 15 msec versus 22 msec for the positive control. One hour following the infusion, the maximum QTc prolongation among telavancin-treated patients was 6 to 9 msec versus 15 msec for the positive control 1.
Common questions
Can I take Amitriptyline and Telavancin together?
Combining amitriptyline and telavancin can add up their effects on heart rhythm (QT prolongation), so if you need both, your care team will monitor your heart closely; keep taking both as prescribed and report any palpitations, dizziness, or fainting. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Amitriptyline and Telavancin interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Amitriptyline and Telavancin interaction managed?
This combination is manageable, and your care team has clear ways to keep you safe: Keep taking both medicines as prescribed unless your doctor or pharmacist tells you otherwise. Your team may check an ECG (heart tracing) and monitor you more closely while you're on both drugs. They may also check blood levels like potassium and magnesium, since low levels can add to the risk. Sometimes the team m… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Amitriptyline or Telavancin need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: VIBATIV IV injection, telavancin IV injection. Theravance, Inc. South San Francisco, CA, 2009.
Keep reading about Amitriptyline
Keep reading about Telavancin
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