Drug information of Amitriptyline

Amitriptyline

Drug group:

Amitriptyline is a tricyclic antidepressant. Amitriptyline affects chemicals in the brain that may be unbalanced in people with depression. Amitriptyline is used to treat symptoms of depression.

Mechanism of effect

Amitriptyline inhibits the membrane pump mechanism responsible for uptake of norepinephrine and serotonin in adrenergic and serotonergic neurons. Pharmacologically, this action may potentiate or prolong neuronal activity since reuptake of these biogenic amines is important physiologically in terminating transmitting activity. This interference with reuptake of norepinephrine and/or serotonin is believed by some to underlie the antidepressant activity of Amitriptyline.

Pharmacodynamic

Amitriptyline HCl is an antidepressant with sedative effects. Its mechanism of action in man is not known. It is not a monoamine oxidase inhibitor and it does not act primarily by stimulation of the central nervous system.

Pharmacokinetics

Rapidly and well absorbed following oral administration (bioavailability is 30-60% due to first pass metabolism). Peak plasma concentrations occur 2-12 hours following oral or intramuscular administration. Very highly protein bound (90% or more) in plasma and tissues. Metabolism: Exclusively hepatic, with first pass effect. Amitriptyline is demethylated in the liver to its primary active metabolite, nortriptyline. Virtually the entire dose is excreted as glucuronide or sulfate conjugate of metabolites, with little unchanged drug appearing in the urine. 25-50% of a single orally administered dose is excreted in urine as inactive metabolites within 24 hours. Small amounts are excreted in feces via biliary elimination. Half life: 10 to 50 hours, with an average of 15 hours.

Drug indications

Depression

Dosage

Usual Adult Dose for Depression
Outpatients:
Usual dose: 75 mg orally per day in divided doses; this may be increased to a total of 150 mg per day if needed
Alternate dose: 40 to 100 mg orally as a single dose at bedtime; this may be increased by 25 or 50 mg as needed at bedtime to a total of 150 mg per day
Maximum dose: 150 mg orally per day
Inpatients:
Initial dose: 100 mg orally per day
Maintenance dose: 40 to 100 mg orally as a single dose at bedtime
Maximum dose: 300 mg orally per day
Usual Geriatric Dose for Depression
10 mg orally 3 times a day with 20 mg at bedtime
Usual Pediatric Dose for Depression
12 years or older:
10 mg orally 3 times a day with 20 mg at bedtime

Interactions

(Atropine sulfate (Ophtalmic , Aripiprazole , Edrophonium , Ergotamine-C , Expectorant , Buspirone , tropisetron , Bepridil , Blonanserin , vemurafenib , vorapaxar , Fedratinib , Levalbuterol , Levomilnacipran , Lorlatinib , glycopyrrolate topical , Gadofosveset , Grepafloxacin , Dexfenfluramine , chlorcyclizine + phenylephrine , Huperzine A , Arformoterol , Benzphetamine , Desvenlafaxine , Xylometazoline , Propylhexedrine , Milnacipran , acrivastine+pseudoephedrine , Halofantrine , lisdexamfetamine , Peginterferon alfa-2b , Triazolam , Lorcaserin , pilocarpine oral , Arsenic trioxide , Benzatropine , Procainamide , Mefloquine , Indapamide , Botulinum toxin , Felbamate , Diethylpropion , Phenindione , Palonosetron , vandetanib , Droperidol , Osimertinib , Tapentadol , safinamide , Ziprasidone , teriflunomide , rasagiline , codeine , Azelastine , Cyclobenzaprine , Ranolazine , potassium citrate , Sodium Oxybate , Toremifene , Clemastine , Clozapine , Yohimbine , formoterol , Rivaroxaban , Disulfiram , Galantamine , Glibenclamide , Modafinil , Mexiletine , Venlafaxine , Chlordiaze poxide , Dobutamine , Atropine/ diphenoxylate( Lomotil® ) , Ranitidine , Sibutramine , Fluvoxamine , Fluoxetine , Pyridostigmine , Tetrabenazine , Trazodone , Tranylcypromine , Triptorelin , Duloxetine , Acetaminophen , Acetaminophen+caffeine , Acetaminophen+caffein+acetylsalic , Acetaminophan+caffeine+ibuprofen , Olanzapine , Ibuprofen , Ipratropium bromide , Indomethacin , Bupropion , Paroxetine , Potassium chloride , Pramipexole , Procarbazine , Piroxicam , Pimozide , Thalidomide , Topiramate , Diclofenac , Zolpidem , Salbutamol , Salmeterol , Cimetidine , Sertraline , Celexib , Cisapride , Cinacalcet , Fluticasone propinate , Phenobarbital , Granisetron , Gliclazide , Levothyroxine , Lithium carbonate , Minocycline , Methyldopa , Mefenamic acid , Meloxicam , Magnesium sulfate , Moclobemide , Midodrine , Naproxen , Naphazoline , Nicorandil , Warfarin , Chlorpheniramine , Clonidine , Linezolid , Quetiapine , Liothyronine

Alerts

1-Patients with major depressive disorder (MDD), both adult and pediatric, may experience worsening of their depression and/or the emergence of suicidal ideation and behavior (suicidality) or unusual changes in behavior .
2- Amitriptyline hydrochloride is not approved for use in treating bipolar depression.
3-Amitriptyline hydrochloride should be used with caution in patients with impaired liver function.

Points of recommendation

1-When possible, the drug should be discontinued several days before elective surgery.
2-Both elevation and lowering of blood sugar levels have been reported.

Pregnancy level

C

Related drugs

Nortriptyline , Amoxapine


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