Norepinephrine and Amitriptyline: 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
Norepinephrine
No brand names on record
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.
Amitriptyline (Elavil) and norepinephrine can push your blood pressure up too high. Amitriptyline is a tricyclic antidepressant. One thing it does is keep norepinephrine, a natural chemical that tightens blood vessels, hanging around longer in the body. So if you also receive norepinephrine as a medicine (sometimes it is even mixed into local anesthetic shots), the effect can be much stronger than expected.
In one study, people on drugs like amitriptyline had a 4 to 8 times bigger blood pressure response. The good news is your care team knows about this. They can avoid the combination or watch your blood pressure very closely and adjust things carefully.
Effect: Severe, prolonged hypertension from potentiation of norepinephrine's pressor response.
Mechanism: TCAs like amitriptyline block presynaptic norepinephrine reuptake, prolonging and amplifying its vasoconstrictor action at the synapse. A clinical trial showed a 4 to 8 fold increase in response to IV norepinephrine in TCA-treated volunteers. Neither agent is activated by the other; this is a pharmacodynamic potentiation.
- Onset: rapid
- Evidence: probable
- Severity: major
Management: Avoid concurrent use, including local anesthetics containing norepinephrine. If unavoidable, use reduced pressor dosing, titrate cautiously, and monitor blood pressure and heart rate continuously.
What happens
Severe, prolonged hypertension
Interaction Deep Dive
Taking norepinephrine1 together with a tricyclic antidepressant, which includes the administration of local anesthetic solutions that contain norepinephrine 2, can result in severe and prolonged hypertension 1. In one clinical trial, volunteers receiving tricyclic antidepressants showed a 4- to 8-fold greater response to IV norepinephrine 3. Close monitoring of patients is warranted when both agents must be used at the same time 2.
Why it happens (mechanism)
Unknown
How to manage this interaction
What your care team may do:
- Avoid the combination when possible, including local anesthetic injections that contain norepinephrine.
- If norepinephrine is truly needed (for example, in an emergency or during a procedure), give it in a carefully controlled, individualized dose.
- Monitor your blood pressure and heart rate closely and adjust the dose as needed.
What you can do: Keep taking your amitriptyline as prescribed. Tell every provider, especially dentists and surgeons, that you take a tricyclic antidepressant, so they can choose a safe anesthetic. Raise any questions with your pharmacist or prescriber.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) Four healthy volunteers were given IV infusions of several sympathomimetic amines (epinephrine, norepinephrine, phenylephrine, and isoproterenol) both before and after receiving imipramine (25 mg three times daily for 5 days). Following imipramine, they exhibited a greater pressor response to epinephrine (2- to 4-fold), norepinephrine (4- to 8-fold), and phenylephrine (2- to 3-fold), while no change was seen in the response to isoproterenol. Consequently, the enhanced pressor response seemed to affect only alpha-adrenergic effects. All 4 participants showed alterations in cardiac rhythm when given epinephrine together with imipramine, which involved sinus arrhythmia in 3 subjects and multiple ectopic beats along with a nodal rhythm in the fourth subject 3.
b) An examination of spontaneous reports concerning adverse reactions to vasoconstrictors contained in local anesthetics identified 15 patients who received a local anesthetic combined with norepinephrine (1:25,000) and experienced severe reactions (severe headaches, chest tightness, subarachnoid hemorrhage). The medication history was incomplete, but at least 3 of them had been using a tricyclic antidepressant at that time 4.
Common questions
Can I take Norepinephrine and Amitriptyline together?
Amitriptyline can greatly amplify norepinephrine's blood-pressure-raising effect, so this combination is usually avoided; if it is needed, expect careful dosing and close monitoring. Always tell dentists and surgeons you take a tricyclic antidepressant. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Norepinephrine and Amitriptyline interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
How is the Norepinephrine and Amitriptyline interaction managed?
What your care team may do: Avoid the combination when possible, including local anesthetic injections that contain norepinephrine. If norepinephrine is truly needed (for example, in an emergency or during a procedure), give it in a carefully controlled, individualized dose. Monitor your blood pressure and heart rate closely and adjust the dose as needed. What you can do: Keep taking your amitript… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Norepinephrine or Amitriptyline 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 (4)
- Product Information: Levophed(TM) intravenous injection, norepinephrine bitartrate intravenous injection. Hospira Inc (per DailyMed), Lake Forest, IL, 2018. DailyMed
- Product Information: Xylocaine(R) with Epinephrine injection solution, lidocaine HCl epinephrine injection solution. Fresenius Kabi (per FDA), Lake Zurich, IL, 2018. DailyMed
- Boakes AJ, Laurence DR, Teoh PC, et al: Interactions between sympathomimetic amines and antidepressant agents in man. Br Med J 1973; 1:311-315. PubMed
- Anon: Vasoconstrictor agents in local-anaesthetic preparations. Lancet 1972; 2:584. DOI
Keep reading about Amitriptyline
Keep reading about Norepinephrine
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