Amitriptilina

Amitriptilina Uses, Dosage, Side Effects, Food Interaction and all others data.

Amitriptilina 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.

Amitriptilina 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 Amitriptilina.

Effects in pain and depression

Amitriptilina is a tricyclic antidepressant and an analgesic. It has anticholinergic and sedative properties .Clinical studies have shown that oral amitriptyline achieves, at a minimum, good to moderate response in up to 2/3 of patients diagnosed with post-herpetic neuralgia and 3/4 of patients diagnosed with diabetic neuropathic pain, and neurogenic pain syndromes that are frequently unresponsive to narcotic analgesics. Amitriptilina has also shown efficacy in diverse groups of patients with chronic non-malignant pain. There have also been some studies showing efficacy in managing fibromyalgia (an off-label use of this drug) , .

Cardiovascular and Anticholinergic Effects

Trade Name Amitriptilina
Availability Prescription only
Generic Amitriptyline
Amitriptyline Other Names Amitriptilina, Amitriptylin, Amitriptyline, Amitriptylinum
Related Drugs Rexulti, Buprenex, aspirin, prednisone, ibuprofen, acetaminophen, sertraline, tramadol, trazodone, fluoxetine
Type
Formula C20H23N
Weight Average: 277.4033
Monoisotopic: 277.183049741
Protein binding

Very highly protein bound (95%) in plasma and tissues .

Groups Approved
Therapeutic Class Tricyclic Anti-depressant
Manufacturer
Available Country
Last Updated: September 19, 2023 at 7:00 am
Amitriptilina
Amitriptilina

How Amitriptilina works

The mechanism of action of this drug is not fully elucidated. It is suggested that amitriptyline inhibits the membrane pump mechanism responsible for the re-uptake of transmitter amines, such as norepinephrine and serotonin, thereby increasing their concentration at the synaptic clefts of the brain , . These amines are important in regulating mood. The monoamine hypothesis in depression, one of the oldest hypotheses, postulates that deficiencies of serotonin (5-HT) and/or norepinephrine (NE) neurotransmission in the brain lead to depressive effects . This drug counteracts these mechanisms, and this may be the mechanism of amitriptyline in improving depressive symptoms.

Whether its analgesic effects are related to its mood-altering activities or attributable to a different, less obvious pharmacological action (or a combination of both) is unknown .

Dosage

Amitriptilina dosage

Depression :

  • Adults: Initially 50-70 mg a day in divided dose or as a single dose at night at bed time.
  • Elderly and adolescents: 25-50 mg daily in divided doses or as single dose at bed time. Dose can be increased gradually as necessary to a maximum of 150-200 mg. Usual maintenance dose is 50-100 mg daily.

Nocturnal enuresis:

  • 6-10 years: 10-20 mg at bed time.
  • 11-16 years: 25-50 mg at bed time for up to 3 months and gradually withdrawn.

Side Effects

  • Cardiovascular reactions: Hypotension, syncope, postural hypotension, hypertension, tachycardia, palpitations, myocardial infarction, arrythmias, and heart block stroke.
  • CNS and neuromuscular: Confusional states, disturbed concentration disorientation, delusions, and hallucinations.
  • Anticholinergic: Dry mouth, blurred vision, mydriasis, increased intraoccular pressure, hyperplasia.
  • Allergic: Skin rash, urticaria, and photosensitization.
  • Haematological: Bone-marrow depression including agranulocytosis, leukopenia, eosinophilia, and thrombocytopenia.
  • Gastrointestinal: Nausea, epigastric distress, vomiting anorexia, diarrhoea.
  • Endocrine: Testicular swelling, gynaecomastia; breast enlargement, galactorrhoea.
  • Other reaction: Dizziness, weakness, fatigue, headache, weight loss

Toxicity

Toxicity Data: Oral TDLO (child): 4167 μg/kg; Oral TDLO (man): 714 μg/kg/1D (intermittent); Oral TDLO (woman): 10 mg/kg .

Ingestion of 750 mg or more by an adult may result in severe toxicity. The effects in overdose are further increased by simultaneous ingestion of alcohol and another psychotropic agent . Symptoms of overdose include abnormally low blood pressure, confusion, convulsions, dilated pupils and other eye problems, disturbed concentration, drowsiness, hallucinations, impaired heart function, rapid or irregular heartbeat, reduced body temperature, stupor, and unresponsiveness or coma, among others , .

Use in pregnancy

For amitriptyline, only limited clinical data are available regarding its use in pregnancy. Amitriptilina is not recommended during pregnancy unless clearly required and only after careful consideration of both risks and benefits .

Use in breastfeeding

Amitriptilina and its metabolites are excreted into breast milk (corresponding to 0.6 % - 1 % of the maternal dose). A risk to the suckling child must be considered. A decision should be made as to whether it is appropriate to discontinue breastfeeding or to discontinue/abstain from the therapy of this medicinal product, considering the benefit of breastfeeding for the child and the benefit of therapy for the woman.

Effects on fertility

Animal studies have shown reproductive toxicity. No data on the effects of amitriptyline on human fertility are available .

Mutagenesis and carcinogenesis

The genotoxic potential of amitriptyline has been investigated in various in vitro and in vivo studies. Although these investigations showed some contradictory results, a potential of amitriptyline to lead to chromosome abnormalities cannot be excluded. Long-term carcinogenicity studies have not been performed to this date .

Precaution

Schizophrenic patients may develop increased symptoms of psychosis; patients with paranoid symptomatology may have an exaggeration of such symptoms. Depressed patients, particularly those with known manic-depressive illness, may experience a shift to mania or hypomania. In these circumstances the dose of Amitriptilina may be reduced or a major tranquilizer such as perphenazine may be administered concurrently.

The possibility of suicide in depressed patients remains until significant remission occurs. Potentially suicidal patients should not have access to large quantities of this drug. Prescriptions should be written for the smallest amount feasible.

Concurrent administration of Amitriptilina hydrochloride and electroshock therapy may increase the hazards associated with such therapy. Such treatment should be limited to patients for whom it is essential.

When possible, the drug should be discontinued several days before elective surgery. Both elevation and lowering of blood sugar levels have been reported. Amitriptilina hydrochloride should be used with caution in patients with impaired liver function.

Interaction

Monoamine oxidase inhibitors can potentiate the effects of Amitriptilina.

Anticholinergic agents: Amitriptylin should not be given with symptomatic agents such as adrenaline, epinephrine, isoprenaline, noradrenaline.

CNS depressant: Amitriptilina may enhance the response to alcohol, barbiturates.

Cemitidine: Cemitidine is reported to reduce hepatic metabolism of certain tricyclic antidepressants.

Food Interaction

  • Avoid alcohol.
  • Avoid St. John's Wort.
  • Limit caffeine intake.
  • Take with food. Food reduces irritation.

Amitriptilina Alcohol interaction

[Moderate] GENERALLY AVOID:

Concomitant use of ethanol and a tricyclic antidepressant (TCA) may result altered TCA plasma levels and efficacy, and additive impairment of motor skills, especially driving skills.

Acute ethanol ingestion may inhibit TCA metabolism, while chronic ingestion of large amounts of ethanol may induce hepatic TCA metabolism.

Patients should be advised to avoid alcohol during TCA therapy.

Alcoholics who have undergone detoxification should be monitored for decreased TCA efficacy.

Dosage adjustments may be required.

Volume of Distribution

The apparent volume of distribution (Vd)β estimated after intravenous administration is 1221 L±280 L; range 769-1702 L (16±3 L/kg) . It is found widely distributed throughout the body . Amitriptilina and the main metabolite nortriptyline pass across the placental barrier and small amounts are present in breast milk .

Elimination Route

Rapidly absorbed following oral administration (bioavailability is 30-60% due to first pass metabolism). Peak plasma concentrations are reached 2-12 hours after oral or intramuscular administration . Steady-state plasma concentrations vary greatly and this variation may be due to genetic differences .

Half Life

The elimination half-life (t1⁄2 β) amitriptyline after peroral administration is about 25 hours (24.65 ± 6.31 hours; range 16.49-40.36 hours) .

Clearance

The mean systemic clearance (Cls) is 39.24 ± 10.18 L/h (range: 24.53-53.73 L/h) . No clear effect of older age on the pharmacokinetics of amitriptyline has been determined, although it is possible that clearance may be decreased .

Elimination Route

Amitriptilina and its metabolites are mainly excreted in the urine. Virtually the entire dose is excreted as glucuronide or sulfate conjugate of metabolites, with approximately 2% of 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 .

Pregnancy & Breastfeeding use

Pregnancy Category C. Amitriptilina is not recommended during pregnancy, especially during the first and third trimester because the safety of Amitriptilina has not been established yet.

Amitriptilina is detectable in breast milk. Because of the serious adverse reactions in infants from Amitriptilina, a decision should be made whether to continue breast feeding or discontinue the drug

Contraindication

Amitriptilina is contraindicated in myocardial infarction; arrythmias, particularly heartblock of any degree; mania; severe liver disease. Initially sedation may effect the ability to drive or operate machinery. It should be used with caution in patients with a history of epilepsy, glaucoma, urinary retention, prostatic hypertrophy, constipation, cardiac disease, diabetes, pregnancy, hepatic impairment, thyroid disease, increased intraoccular pressure, psychoses (may aggravate mania).

Storage Condition

Keep containers well closed and stored below 25˚ C, protected from light.

Innovators Monograph

You find simplified version here Amitriptilina

Amitriptilina contains Amitriptyline see full prescribing information from innovator Amitriptilina Monograph, Amitriptilina MSDS, Amitriptilina FDA label

FAQ

What is Amitriptilina used for?

Amitriptilina is a tricyclic antidepressant primarily used to treat major depressive disorder and a variety of pain syndromes from neuropathic pain to fibromyalgia to migraine and tension headaches.
Amitriptilina is a medicine used for treating pain. You can also take it Amitriptilina to treat nerve pain (neuralgia) and back pain.

How safe is Amitriptilina?

Amitriptilina is safe to take for a long time. There do not seem to be any lasting harmful effects from taking it for many months or years.

How does Amitriptilina work?

Amitriptilina work by increasing a chemical called serotonin in your brain.

What are the common side effects of Amitriptilina?

Common side effects of Amitriptilina are include:

  • constipation.
  • dizziness.
  • dry mouth.
  • feeling sleepy.
  • difficulty peeing.
  • headache.

Is Amitriptilina safe during pregnancy?

Amitriptilina is generally not recommended in pregnancy. This is because it has been linked to a small risk of problems for your baby if you take it in early or late pregnancy.

Is Amitriptilina safe during breastfeeding?

Amitriptilina is not usually recommended if you're breastfeeding. Amitriptilina gets into breast milk. It's been linked with side effects like sleepiness in breastfed babies.

Can I drink alcohol with Amitriptilina?

You can drink alcohol while taking Amitriptilina but it may make you feel sleepy. It's usually best to stop drinking alcohol until you see how the medicine makes you feel.

Can I drive after taking Amitriptilina ?

Some people feel sleepy while they're taking Amitriptilina. It is best to stop driving and cycling for the first few days of treatment until you know how this medicine makes you feel.

When should be taken of Amitriptilina?

It's best to take it before bedtime because it can make you feel sleepy. If you find that you are still feeling drowsy in the morning you could try taking it earlier in the evening.

Can I take Amitriptilina on an empty stomach?

Amitriptilina may be taken on an empty or full stomach.

How many time can I take Amitriptilina daily?

Amitriptilina is usually taken one to four times a day.

How long does Amitriptilina take to work?

You may start to feel better after 1 to 2 weeks but it can take 4 to 6 weeks for Amitriptilina to work fully.

How long does Amitriptilina take to work?

So Amitriptilina will stay in your system for about 2 to 6 days after your last dose.

How much Amitriptilina can I take daily?

Adults, At first  75 milligrams (mg) per day given in divided doses, or 50 to 100 mg at bedtime.

How long can I take Amitriptilina?

Some people take it for many months and even for years. You should take this medication for at least 3-6 months.

Who should not take Amitriptilina?

You should not use Amitriptilina if you have recently had a heart attack. Do not use Amitriptilina if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.


What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention. An overdose of amitriptyline can be fatal. Overdose symptoms may include irregular heart rhythm, feeling like you might pass out, seizures, or coma.

What happen If I stop taking Amitriptilina?

Amitriptilina is not addictive but you can get extra side effects if you stop taking it suddenly. You may have flu-like symptoms like feeling sick, muscle pain and feeling tired or restless.

Will Amitriptilina affect my fertility?

There is no clear evidence that Amitriptilina affects either male or female fertility.

Does Amitriptilina cause heart attacks?

Amitriptilina induced toxic myocarditis and dilated cardiomyopathy have been reported only once in the literature after autopsy.

Can Amitriptilina affect my kidneys?

Amitriptilina has many side effects on rat liver and kidney, it induced liver and kidney toxicity and tissue injury were it metabolized to nortriptyline which inhibits the reuptake of norepinephrine and serotonin almost equally.

Can Amitriptilina increase blood pressure?

Amitriptilina works to cause very high blood pressure.

Can Amitriptilina gain my weight?

Brand can causes weight gain also with other side effects. 

*** Taking medicines without doctor's advice can cause long-term problems.
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