Nortriptyline

Evidence Level: L2

Predicted Indications: 2

Nortriptyline

Pharmacist Assessment Report

Nortriptyline: Attention deficit-hyperactivity disorder

One-Sentence Summary

Nortriptyline is a tricyclic antidepressant whose original indications in the knowledge base include anxiety disorder, neurotic disorder and dysthymic disorder. The TxGNN model predicts it may be effective for attention deficit hyperactivity disorder (ADHD), with no registered clinical trials but 16 publications (including one randomized controlled trial and one Cochrane systematic review) currently supporting this direction.

Quick Overview

Item	Content
Original Indication	Not recorded in the local data
Predicted New Indication	Attention deficit-hyperactivity disorder
TxGNN Prediction Score	0.9942
Evidence Level	L2
Canada Market Status	Marketed (marketed DINs: 2 of 2)
Number of DINs	2 (marketed: 2)
Recommended Decision	Proceed with Guardrails

Why is This Prediction Reasonable?

Detailed mechanism of action data is not available in the data compiled for this report. Based on general pharmacology, nortriptyline is a tricyclic antidepressant that mainly inhibits norepinephrine reuptake, with weaker serotonin reuptake inhibition. This mechanism is inferred from general knowledge, not from the supplied record.

Enhancing noradrenergic signalling in prefrontal circuits is a recognised approach in ADHD treatment, comparable to atomoxetine. One PET study in the literature also reports that nortriptyline is a norepinephrine-transporter-selective tricyclic agent, which supports a plausible biological link.

The original indications (anxiety and mood-related disorders) and ADHD are both neuropsychiatric conditions in which monoamine modulation plays a role. The high TxGNN score is a computational prediction. It supports prioritisation but does not prove efficacy.

A second predicted entry, ADHD, inattentive type (score 0.9933), follows the same mechanistic rationale. It has no specific supporting evidence, so it is treated as a subset of the main ADHD prediction.

Clinical Trial Evidence

Currently no related clinical trials registered.

Literature Evidence

PMID	Year	Type	Journal	Key Findings
11052409	2000	RCT	J Child Adolesc Psychopharmacol	Controlled study of nortriptyline’s efficacy and tolerability in children and adolescents with ADHD
22700161	2012	RCT	Pediatr Nephrol	Randomized double-blind trial of nortriptyline for enuresis in children with ADHD
25238582	2014	Systematic review	Cochrane Database Syst Rev	Review of tricyclic antidepressants as second-line ADHD treatment in children and adolescents
15064003	2004	Review	Psychiatr Clin North Am	Nonstimulant treatments for adult ADHD; nortriptyline and desipramine are established alternatives but limited by a narrow therapeutic index and cardiovascular toxicity
12270803	2002	Review	Adolesc Med	Overview of ADHD drugs in adolescents, including nortriptyline among the tricyclics
22303520	2012	Guideline	Ann Clin Psychiatry	CANMAT recommendations for mood disorders with comorbid ADHD
8428873	1993	Cohort/Open-label	J Am Acad Child Adolesc Psychiatry	Nortriptyline in children with ADHD and tic disorder or Tourette’s syndrome
8444763	1993	Chart review	J Am Acad Child Adolesc Psychiatry	Chart review of 58 cases of nortriptyline treatment for ADHD
8444754	1993	Retrospective study	J Am Acad Child Adolesc Psychiatry	Serum levels and ECG effects of nortriptyline in children and adolescents
4075308	1985	Clinical study	Clin Neuropharmacol	Early report of nortriptyline in attention deficit disorder

Canada Market Information

DIN	Product Name	Dosage Form	Approved Indication
00015237	AVENTYL	Not listed	Not listed
00015229	AVENTYL	Not listed	Not listed

Safety Considerations

Contraindications (drug-disease associations, not label text): The drug-disease contraindication links include long QT syndrome (including familial), torsades de pointes, heart conduction disease, sudden cardiac arrest, myocardial infarction and coronary thrombosis, stroke and other cerebrovascular disorders, liver failure, kidney failure and uremia, epilepsy, manic bipolar disorder, open-angle glaucoma and glaucoma, benign prostatic hyperplasia, substance abuse/dependence, hyperthyroidism (including Graves disease and thyrotoxicosis), and hemoglobinopathy.
Drug Interactions: 100 interactions were found in total. Of the 20 reviewed, the Major interactions are:
- Epinephrine
- Bupropion
- Lorcaserin
- Potassium citrate
- Dolasetron
Moderate interactions include anticholinergics (atropine, hyoscyamine, glycopyrronium, dicyclomine), loperamide, morphine, famotidine and cimetidine, clarithromycin, chlorpropamide, and others.
Cardiovascular concern in ADHD use: The literature notes that tricyclics have a narrow therapeutic index and potential cardiovascular toxicity, and one retrospective study examined ECG effects in children and adolescents.

Package insert warnings were not available for this report. Please refer to the Health Canada package insert for the full warnings.

Conclusion and Next Steps

Decision: Proceed with Guardrails

Rationale: Published evidence includes a controlled study, a Cochrane review and several clinical series supporting nortriptyline in ADHD, with a plausible noradrenergic mechanism. However, there are no registered clinical trials, and the cardiovascular and interaction risks are significant. The inattentive-type prediction has no specific evidence, so it should be held.

To proceed, the following is needed:

Health Canada package insert warnings and contraindications (a blocking gap for safety screening)
Confirmed mechanism of action data from DrugBank
A careful review of the RCT and Cochrane review findings to confirm effect size and tolerability
A cardiovascular (ECG) and drug-interaction monitoring plan, especially for children and adolescents
Confirmation of the approved indications and dosage forms of the two AVENTYL DINs
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.