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ALERT: U.S. Boxed Warning
The FDA-approved labeling includes a boxed warning. See Warnings/Precautions section for a concise summary of this information. For verbatim wording of the boxed warning, consult the product labeling or www.fda.gov.
Medication Safety Issues
Sound-alike/look-alike issues:
Amitriptyline may be confused with aminophylline, imipramine, nortriptyline
Elavil® may be confused with Aldoril®, Eldepryl®, enalapril, Equanil®, Mellaril®, Plavix®
Pronunciation
(a mee TRIP ti leen)
Index Terms
Generic Available
Yes
Canadian Brand Names
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Relief of symptoms of depression
Use: Dental
Management of chronic neuropathic pain in temporomandibular dysfunction (TMD)
Use: Unlabeled/Investigational
Analgesic for certain chronic and neuropathic pain; prophylaxis against migraine headaches; treatment of depressive disorders in children; post-traumatic stress disorder (PTSD)
Pregnancy Risk Factor
C
Pregnancy Considerations
Teratogenic effects have been observed in animal studies. Amitriptyline crosses the human placenta; CNS effects, limb deformities and developmental delay have been noted in case reports.
Lactation
Enters breast milk/not recommended (AAP rates “of concern”)
Breast-Feeding Considerations
Generally, it is not recommended to breast-feed if taking antidepressants because of the long half-life, active metabolites, and the potential for side effects in the infant.
Contraindications
Hypersensitivity to amitriptyline or any component of the formulation (cross-sensitivity with other tricyclics may occur); use of MAO inhibitors within past 14 days; acute recovery phase following myocardial infarction; concurrent use of cisapride
Warnings/Precautions
Boxed warnings:
• Suicidal thinking/behavior: See “Major psychiatric warnings” below.
Major psychiatric warnings:
• [U.S. Boxed Warning]: Antidepressants increase the risk of suicidal thinking and behavior in children, adolescents, and young adults (18-24 years of age) with major depressive disorder (MDD) and other psychiatric disorders; consider risk prior to prescribing. Short-term studies did not show an increased risk in patients >24 years of age and showed a decreased risk in patients ?65 years. Closely monitor patients for clinical worsening, suicidality, or unusual changes in behavior, particularly during the initial 1-2 months of therapy or during periods of dosage adjustments (increases or decreases); the patient's family or caregiver should be instructed to closely observe the patient and communicate condition with healthcare provider. A medication guide concerning the use of antidepressants should be dispensed with each prescription. Amitriptyline is not FDA-approved for use in children <12 years of age.
• The possibility of a suicide attempt is inherent in major depression and may persist until remission occurs. Patients treated with antidepressants should be observed for clinical worsening and suicidality, especially during the initial few months of a course of drug therapy, or at times of dose changes, either increases or decreases. Worsening depression and severe abrupt suicidality that are not part of the presenting symptoms may require discontinuation or modification of drug therapy. Use caution in high-risk patients during initiation of therapy.
• Prescriptions should be written for the smallest quantity consistent with good patient care. The patient's family or caregiver should be alerted to monitor patients for the emergence of suicidality and associated behaviors such as anxiety, agitation, panic attacks, insomnia, irritability, hostility, impulsivity, akathisia, hypomania, and mania; patients should be instructed to notify their healthcare provider if any of these symptoms or worsening depression or psychosis occur.
• May worsen psychosis in some patients or precipitate a shift to mania or hypomania in patients with bipolar disorder. Monotherapy in patients with bipolar disorder should be avoided. Patients presenting with depressive symptoms should be screened for bipolar disorder. Amitriptyline is not FDA approved for the treatment of bipolar depression.
Concerns related to adverse effects:
• Anticholinergic effects: May cause anticholinergic effects (constipation, xerostomia, blurred vision, urinary retention); use with caution in patients with decreased gastrointestinal motility, paralytic ileus, urinary retention, BPH, xerostomia, or visual problems. The degree of anticholinergic blockade produced by this agent is high relative to other antidepressants.
• Hematologic effects: TCAs may rarely cause bone marrow suppression; monitor for any signs of infection and obtain CBC if symptoms (eg, fever, sore throat) evident.
• Orthostatic hypotension: May cause orthostatic hypotension (risk is very high relative to other antidepressants); use with caution in patients at risk of this effect or in those who would not tolerate transient hypotensive episodes (cerebrovascular disease, cardiovascular disease, hypovolemia, or concurrent medication use which may predispose to hypotension/bradycardia).
• Sedation: May cause sedation, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving). The degree of sedation is very high relative to other antidepressants.
Disease-related concerns:
• Cardiovascular disease: Use with caution in patients with a history of cardiovascular disease (including previous MI, stroke, tachycardia, or conduction abnormalities); the risk of conduction abnormalities with this agent is high relative to other antidepressants.
• Diabetes: Use with caution in patients with diabetes mellitus; may alter glucose regulation.
• Hepatic impairment: Use with caution in patients with hepatic impairment.
• Renal impairment: Use with caution in patients with renal impairment.
• Seizure disorder: Use with caution in patients at risk of seizures, including those with a history of seizures, head trauma, brain damage, alcoholism, or concurrent therapy with medications which may lower seizure threshold.
• Thyroid dysfunction: Use with caution in patients with hyperthyroidism or those receiving thyroid supplementation due to concerns of pro-arrhythmogenesis.
Concurrent drug therapy issues:
• Anticholinergic and/or neuroleptic agents: Hyperpyrexia has been observed with TCAs in combination with anticholinergics and/or neuroleptics, particularly during hot weather.
• Sedatives: Effects may be potentiated when used with other sedative drugs or ethanol.
Special populations:
• Elderly: Use with caution in the elderly.
Other warnings/precautions:
• Discontinuation of therapy: Recommended to discontinue prior to elective surgery requiring general anesthesia. Therapy should not be abruptly discontinued in patients receiving high doses for prolonged periods.
• Electroconvulsive therapy: May increase the risks associated with electroconvulsive therapy; consider discontinuing, when possible, prior to ECT treatment.
Adverse Reactions
Anticholinergic effects may be pronounced; moderate to marked sedation can occur (tolerance to these effects usually occurs).
Frequency not defined.
Cardiovascular: Orthostatic hypotension, tachycardia, ECG changes (nonspecific), AV conduction changes, cardiomyopathy (rare), MI, stroke, heart block, arrhythmia, syncope, hypertension, palpitation
Central nervous system: Restlessness, dizziness, insomnia, sedation, fatigue, anxiety, cognitive function impaired, seizure, extrapyramidal symptoms, coma, hallucinations, confusion, disorientation, coordination impaired, ataxia, headache, nightmares, hyperpyrexia
Dermatologic: Allergic rash, urticaria, photosensitivity, alopecia
Endocrine & metabolic: Syndrome of inappropriate ADH secretion
Gastrointestinal: Weight gain, xerostomia, constipation, paralytic ileus, nausea, vomiting, anorexia, stomatitis, peculiar taste, diarrhea, black tongue
Genitourinary: Urinary retention
Hematologic: Bone marrow depression, purpura, eosinophilia
Neuromuscular & skeletal: Numbness, paresthesia, peripheral neuropathy, tremor, weakness
Ocular: Blurred vision, mydriasis, ocular pressure increased
Otic: Tinnitus
Miscellaneous: Diaphoresis, withdrawal reactions (nausea, headache, malaise)
Postmarketing and/or case reports: Neuroleptic malignant syndrome (rare), serotonin syndrome (rare)
Metabolism/Transport Effects
Substrate of CYP1A2 (minor), 2B6 (minor), 2C9 (minor), 2C19 (minor), 2D6 (major), 3A4 (minor); Inhibits CYP1A2 (weak), 2C9 (weak), 2C19 (weak), 2D6 (weak), 2E1 (weak)
Drug Interactions
Acetylcholinesterase Inhibitors (Central): Anticholinergics may diminish the therapeutic effect of Acetylcholinesterase Inhibitors (Central). Acetylcholinesterase Inhibitors (Central) may diminish the therapeutic effect of Anticholinergics. If the anticholinergic action is a side effect of the agent, the result may be beneficial. Risk C: Monitor therapy
Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Risk C: Monitor therapy
Alfuzosin: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk C: Monitor therapy
Alpha-/Beta-Agonists (Direct-Acting): Tricyclic Antidepressants may enhance the vasopressor effect of Alpha-/Beta-Agonists (Direct-Acting). Exceptions: Dipivefrin. Risk D: Consider therapy modification
Alpha1-Agonists: Tricyclic Antidepressants may enhance the vasopressor effect of Alpha1-Agonists. Risk D: Consider therapy modification
Alpha2-Agonists: Tricyclic Antidepressants may diminish the antihypertensive effect of Alpha2-Agonists. Exceptions: Apraclonidine; Brimonidine. Risk D: Consider therapy modification
Altretamine: May enhance the orthostatic effect of Tricyclic Antidepressants. Risk C: Monitor therapy
Amphetamines: Tricyclic Antidepressants may enhance the stimulatory effect of Amphetamines. Tricyclic Antidepressants may also potentiate the cardiovascular effects of Amphetamines. Risk C: Monitor therapy
Anticholinergics: May enhance the adverse/toxic effect of other Anticholinergics. Exceptions: Paliperidone. Risk C: Monitor therapy
Artemether: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk X: Avoid combination
Aspirin: Antidepressants (Tricyclic, Tertiary Amine) may enhance the antiplatelet effect of Aspirin. Risk C: Monitor therapy
Barbiturates: May increase the metabolism of Tricyclic Antidepressants. Risk D: Consider therapy modification
Beta2-Agonists: Tricyclic Antidepressants may enhance the adverse/toxic effect of Beta2-Agonists. Risk C: Monitor therapy
BuPROPion: May decrease the metabolism of Tricyclic Antidepressants. Risk C: Monitor therapy
CarBAMazepine: May increase the metabolism of Tricyclic Antidepressants. Risk C: Monitor therapy
Chloroquine: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk C: Monitor therapy
Cimetidine: May decrease the metabolism of Tricyclic Antidepressants. Risk C: Monitor therapy
Cinacalcet: May increase the serum concentration of Tricyclic Antidepressants. Risk C: Monitor therapy
Ciprofloxacin: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk C: Monitor therapy
Cisapride: Amitriptyline may enhance the arrhythmogenic effect of Cisapride. Risk X: Avoid combination
CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Risk C: Monitor therapy
CYP2D6 Inhibitors (Moderate): May decrease the metabolism of CYP2D6 Substrates. Risk C: Monitor therapy
CYP2D6 Inhibitors (Strong): May decrease the metabolism of CYP2D6 Substrates. Risk D: Consider therapy modification
Desmopressin: Tricyclic Antidepressants may enhance the adverse/toxic effect of Desmopressin. Risk C: Monitor therapy
Dexmethylphenidate: May decrease the metabolism of Tricyclic Antidepressants. Risk C: Monitor therapy
Dronedarone: QTc-Prolonging Agents may enhance the QTc-prolonging effect of Dronedarone. Risk X: Avoid combination
DULoxetine: May decrease the metabolism of Tricyclic Antidepressants. Risk C: Monitor therapy
Gadobutrol: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk D: Consider therapy modification
Iobenguane I 123: Tricyclic Antidepressants may diminish the therapeutic effect of Iobenguane I 123. Risk X: Avoid combination
Lithium: May enhance the neurotoxic effect of Tricyclic Antidepressants. Risk C: Monitor therapy
Lumefantrine: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk X: Avoid combination
MAO Inhibitors: May enhance the serotonergic effect of Tricyclic Antidepressants. This may cause serotonin syndrome. Risk X: Avoid combination
MAO Inhibitors: May enhance the orthostatic effect of Orthostasis Producing Agents. Risk C: Monitor therapy
Methylphenidate: May decrease the metabolism of Tricyclic Antidepressants. Risk C: Monitor therapy
Nilotinib: May enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk X: Avoid combination
NSAID (COX-2 Inhibitor): Antidepressants (Tricyclic, Tertiary Amine) may enhance the antiplatelet effect of NSAID (COX-2 Inhibitor). Risk C: Monitor therapy
NSAID (Nonselective): Antidepressants (Tricyclic, Tertiary Amine) may enhance the antiplatelet effect of NSAID (Nonselective). Risk C: Monitor therapy
Peginterferon Alfa-2b: May decrease the serum concentration of CYP2D6 Substrates. Risk C: Monitor therapy
Pimozide: QTc-Prolonging Agents may enhance the QTc-prolonging effect of Pimozide. Risk X: Avoid combination
Pramlintide: May enhance the anticholinergic effect of Anticholinergics. These effects are specific to the GI tract. Risk D: Consider therapy modification
Propoxyphene: May enhance the CNS depressant effect of Tricyclic Antidepressants. Risk C: Monitor therapy
Protease Inhibitors: May increase the serum concentration of Tricyclic Antidepressants. Risk C: Monitor therapy
QTc-Prolonging Agents: May enhance the adverse/toxic effect of other QTc-Prolonging Agents. Their effects can be additive, causing life-threatening ventricular arrhythmias. Risk D: Consider therapy modification
QuiNIDine: Tricyclic Antidepressants may enhance the QTc-prolonging effect of QuiNIDine. QuiNIDine may decrease the metabolism of Tricyclic Antidepressants. Risk D: Consider therapy modification
QuiNINE: QTc-Prolonging Agents may enhance the QTc-prolonging effect of QuiNINE. QuiNINE may enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk X: Avoid combination
Selective Serotonin Reuptake Inhibitors: May decrease the metabolism of Tricyclic Antidepressants. Risk D: Consider therapy modification
Serotonin Modulators: May enhance the adverse/toxic effect of other Serotonin Modulators. The development of serotonin syndrome may occur. Risk D: Consider therapy modification
Sibutramine: May enhance the serotonergic effect of Serotonin Modulators. This may cause serotonin syndrome. Risk X: Avoid combination
St Johns Wort: May increase the metabolism of Tricyclic Antidepressants. The risk of serotonin syndrome may theoretically be increased. Risk D: Consider therapy modification
Sulfonylureas: Cyclic Antidepressants may enhance the hypoglycemic effect of Sulfonylureas. Risk C: Monitor therapy
Terbinafine: May decrease the metabolism of Tricyclic Antidepressants. Risk D: Consider therapy modification
Tetrabenazine: QTc-Prolonging Agents may enhance the QTc-prolonging effect of Tetrabenazine. Risk X: Avoid combination
Thioridazine: QTc-Prolonging Agents may enhance the QTc-prolonging effect of Thioridazine. Risk X: Avoid combination
TraMADol: Tricyclic Antidepressants may enhance the neuroexcitatory and/or seizure-potentiating effect of TraMADol. Risk C: Monitor therapy
Valproic Acid: May increase the serum concentration of Tricyclic Antidepressants. Risk C: Monitor therapy
Vitamin K Antagonists (eg, warfarin): Tricyclic Antidepressants may enhance the anticoagulant effect of Vitamin K Antagonists. Risk C: Monitor therapy
Yohimbine: Tricyclic Antidepressants may increase the serum concentration of Yohimbine. Risk C: Monitor therapy
Ziprasidone: QTc-Prolonging Agents may enhance the QTc-prolonging effect of Ziprasidone. The risk of a severe arrhythmia may be increased. Risk X: Avoid combination
Ethanol/Nutrition/Herb Interactions
Ethanol: Avoid ethanol (may increase CNS depression).
Food: Grapefruit juice may inhibit the metabolism of some TCAs and clinical toxicity may result.
Herb/Nutraceutical: St John's wort may decrease amitriptyline levels. Avoid valerian, St John's wort, kava kava, gotu kola (may increase CNS depression).
Mechanism of Action
Increases the synaptic concentration of serotonin and/or norepinephrine in the central nervous system by inhibition of their reuptake by the presynaptic neuronal membrane
Pharmacodynamics/Kinetics
Onset of action: Migraine prophylaxis: 6 weeks, higher dosage may be required in heavy smokers because of increased metabolism; Depression: 4-6 weeks, reduce dosage to lowest effective level
Distribution: Crosses placenta; enters breast milk
Metabolism: Hepatic to nortriptyline (active), hydroxy and conjugated derivatives; may be impaired in the elderly
Half-life elimination: Adults: 9-27 hours (average: 15 hours)
Time to peak, serum: ~4 hours
Excretion: Urine (18% as unchanged drug); feces (small amounts)
Dosage
Children:
Chronic pain management (unlabeled use): Oral: Initial: 0.1 mg/kg at bedtime, may advance as tolerated over 2-3 weeks to 0.5-2 mg/kg at bedtime
Depressive disorders (unlabeled use): Oral: Initial doses of 1 mg/kg/day given in 3 divided doses with increases to 1.5 mg/kg/day have been reported in a small number of children (n=9) 9-12 years of age; clinically, doses up to 3 mg/kg/day (5 mg/kg/day if monitored closely) have been proposed
Migraine prophylaxis (unlabeled use): Oral: Initial: 0.25 mg/kg/day, given at bedtime; increase dose by 0.25 mg/kg/day to maximum 1 mg/kg/day. Reported dosing ranges: 0.1-2 mg/kg/day; maximum suggested dose: 10 mg.
Adolescents: Depressive disorders: Oral: Initial: 25-50 mg/day; may administer in divided doses; increase gradually to 100 mg/day in divided doses
Adults:
Depression: Oral: 50-150 mg/day single dose at bedtime or in divided doses; dose may be gradually increased up to 300 mg/day
Chronic pain management (unlabeled use): Oral: Initial: 25 mg at bedtime; may increase as tolerated to 100 mg/day
Migraine prophylaxis (unlabeled use): Oral: Initial: 10-25 mg at bedtime; usual dose: 150 mg; reported dosing ranges: 10-400 mg/day
Post-traumatic stress disorder (PTSD) (unlabeled use): Oral: 75-200 mg/day
Elderly: Depression: Oral: Initial: 10-25 mg at bedtime; dose should be increased in 10-25 mg increments every week if tolerated; dose range: 25-150 mg/day
Dosing interval in hepatic impairment: Use with caution and monitor plasma levels and patient response
Hemodialysis: Nondialyzable
Dental Usual Dosing
Chronic neuropathic pain in temporomandibular dysfunction (TMD) (unlabeled use): Adults: Oral: Initial: 25 mg at bedtime; may increase as tolerated to 100 mg/day
Monitoring Parameters
Monitor blood pressure and pulse rate prior to and during initial therapy; evaluate mental status, suicidal ideation (especially at the beginning of therapy or when doses are increased or decreased); monitor weight; ECG in older adults and patients with cardiac disease
Reference Range
Therapeutic: Amitriptyline and nortriptyline 100-250 ng/mL (SI: 360-900 nmol/L); nortriptyline 50-150 ng/mL (SI: 190-570 nmol/L); Toxic: >0.5 mcg/mL; plasma levels do not always correlate with clinical effectiveness
Test Interactions
May cause false-positive reaction to EMIT immunoassay for imipramine
Patient Education
Take exactly as directed; do not increase dose or frequency. It may take several weeks to achieve desired results. Restrict use of alcohol and caffeine; avoid grapefruit juice. Maintain adequate hydration unless instructed to restrict fluid intake. If you have diabetes, monitor glucose levels closely; this medication may alter glucose levels. May turn urine blue-green (normal). May cause drowsiness, lightheadedness, impaired coordination, dizziness, or blurred vision (use caution when driving or engaging in tasks requiring alertness until response to drug is known); constipation (increased exercise, fluids, fruit, or fiber may help); urinary retention (void before taking medication); postural hypotension (use caution climbing stairs or when changing position from lying or sitting to standing); altered sexual drive or ability (reversible); or photosensitivity (use sunscreen, wear protective clothing and eyewear, and avoid direct sunlight). Report persistent CNS effects (eg, nervousness, restlessness, insomnia, headache, agitation, impaired coordination, changes in cognition); suicidal ideation; muscle cramping, weakness, tremors, or rigidity; ringing in ears or visual disturbances; chest pain, palpitations, or irregular heartbeat; blurred vision; or worsening of condition. Pregnancy/breast-feeding precautions: Do not get pregnant while taking this medication. Consult prescriber for appropriate contraceptive measures. Breast-feeding is not recommended.
Geriatric Considerations
Not a drug of choice for elderly. The most anticholinergic and sedating of the antidepressants; pronounced effects on the cardiovascular system (hypotension), hence, many geropsychiatrists agree it is best to avoid in elderly.
Anesthesia and Critical Care Concerns/Other Considerations
Desired therapeutic effect (for analgesia) may take as long as 1-3 weeks. When used for migraine headache prophylaxis, therapeutic effect may take as long as 6 weeks.
Tricyclic antidepressants affect conduction and have anticholinergic effects and, therefore, should be used with caution in patients with underlying cardiovascular disease. Therapy is relatively contraindicated in patients with conduction abnormalities or in patients with symptomatic hypotension. Heart block may be precipitated in patients with pre-existing conduction system disease.
Cardiovascular Considerations
Frequently, low doses of tricyclics are used for the treatment of muscle cramps, neuralgia, etc. These low doses are not innocuous and may result in resting tachycardia and significant orthostatic hypotension. This is especially a problem in elderly patients on tricyclics and in patients who have coexisting diuretic therapy. Tricyclic antidepressants affect conduction and have anticholinergic effects and, therefore, should be used with caution in patients with underlying cardiovascular disease. Therapy is relatively contraindicated in patients with conduction abnormalities or in patients with symptomatic hypotension. Heart block may be precipitated in patients with pre-existing conduction system disease. Hemodynamics and cardiac conduction should be evaluated during therapy and before dose titration, particularly in patients with cardiovascular disease.
Dental Health: Effects on Dental Treatment
Key adverse event(s) related to dental treatment: Xerostomia and changes in salivation (normal salivary flow resumes upon discontinuation), orthostatic hypotension, stomatitis, peculiar taste, and black tongue. Amitriptyline is the most anticholinergic and sedating of the antidepressants; has pronounced effects on the cardiovascular system. Long-term treatment with TCAs such as amitriptyline increases the risk of caries by reducing salivation and salivary buffer capacity. In a study by Rundergren, et al, pathological alterations were observed in the oral mucosa of 72% of 58 patients; 55% had new carious lesions after taking TCAs for a median of 51/2 years. Current research is investigating the use of the salivary stimulant pilocarpine (Salagen®) to overcome the xerostomia from amitriptyline.
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
Amitriptyline is one of the drugs confirmed to prolong the QT interval and is accepted as having a risk of causing torsade de pointes. In terms of epinephrine, it is not known what effect vasoconstrictors in the local anesthetic regimen will have in patients with a known history of congenital prolonged QT interval or in patients taking any medication that prolongs the QT interval. Until more information is obtained, it is suggested that the clinician consult with the physician prior to the use of a vasoconstrictor in suspected patients, and that the vasoconstrictor (epinephrine, mepivacaine and levonordefrin [Carbocaine® 2% with Neo-Cobefrin®]) be used with caution. See Dental Health Professional Considerations.
Dental Comment
Amitriptyline is known to prolong the QT interval. The QT interval is measured as the time and distance between the Q point of the QRS complex and the end of the T wave in the ECG tracing. After adjustment for heart rate, the QT interval is defined as prolonged if it is more than 450 msec in men and 460 msec in women. A long QT syndrome was first described in the 1950s and 60s as a congenital syndrome involving QT interval prolongation and syncope and sudden death. Some of the congenital long QT syndromes were characterized by a peculiar electrocardiographic appearance of the QRS complex involving a premature atria beat followed by a pause, then a subsequent sinus beat showing marked QT prolongation and deformity. This type of cardiac arrhythmia was originally termed “torsade de pointes” (translated from the French as “twisting of the points”). Amitriptyline is considered as having a risk of causing torsade de pointes. Since it is not known what effect vasoconstrictors in the local anesthetic regimen will have in patients with a known history of congenital prolonged QT interval or in patients taking any medication that prolongs the QT interval, a medical consult is suggested.
Mental Health: Comment
Tricyclic antidepressants may be classified as tertiary (amitriptyline, doxepin, clomipramine, imipramine, trimipramine) or secondary amines (nortriptyline, desipramine, protriptyline). The tertiary amines are not recommended to treat depression in the elderly. If a TCA is used in the elderly, it should be a secondary amine. The tertiary amines are commonly used in low dosages for various conditions associated with pain. Toxicity is generally dose dependent. Relatively small overdoses (1-week supply) can be potentially fatal.
Nursing: Physical Assessment/Monitoring
Assess other medications patient may be taking for effectiveness and interactions. Assess for suicidal tendencies or unusual changes in behavior before beginning therapy and periodically thereafter. May cause physiological or psychological dependence, tolerance, or abuse; evaluate need for continued use periodically. Caution patients with diabetes; may alter serum glucose levels. Monitor therapeutic response and adverse reactions at beginning of therapy and periodically with long-term use. Taper dosage slowly when discontinuing. Teach patient appropriate use, interventions to reduce side effects, and adverse symptoms to report.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, as hydrochloride: 10 mg, 25 mg, 50 mg, 75 mg, 100 mg, 150 mg
Pricing: U.S. (www.drugstore.com)
Tablets (Amitriptyline HCl)
10 mg (30): $11.99
25 mg (90): $11.99
50 mg (90): $12.99
75 mg (100): $14.44
100 mg (30): $13.99
150 mg (90): $21.98
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International Brand Names
Lexi-Comp.com
Last full review/revision November 2009
Content last modified November 2009
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