name, interaction, when to take this antidepressant?

What is amitriptyline?

Amitriptyline is a psychotropic drugmore specifically a antidepressant from the family of tricyclics, also called imipramines. This molecule is also used as analgesic (treatment of pain).

How does amitriptyline work?

Amitriptyline acts on the central nervous system to modulate brain activity. It is a serotonin and norepinephrine reuptake inhibitor, thus increasing the concentrations of these two neurotransmitters in the brain. The increase in levels of serotonin (called the happiness hormone) and norepinephrine help regulate emotions and reduce depression.

Indications: when to take amitriptyline?

This drug has several indications in adults:

• treatment of episodes major depressive
• treatment of neuropathic pain
• treatment preventative of tension headaches
• basic treatment of migraine

Amitriptyline is also prescribed in children from the age of 6 to treat thenocturnal enuresis (involuntary emission of urine) after ruling out any cause relating to an organ.

What is the trade name of amitriptyline?

Amitriptyline exists in the form of tablets and oral drops. The commercial specialties that contain it are Elavil® and Laroxyl® (at dosages 25 mg, 50 mg and 40 mg/mL).

In adults, the maximum dose is 150 mg per day and vigilance is required from 100 mg. In the childthe administration is only reserved for the treatment of nocturnal enuresis (involuntary emission of urine) and should not exceed 50 mg per day. In general, the increase in dosage is carried out very gradually, every 3 to 7 days. Similarly, when treatment is stopped, the dosage is reduced over several weeks. In order to avoid the occurrence of undesirable effects, the maintenance dose should be as low as possible. The oral solution is used when taking tablets (dosage of 25 mg and 50 mg) does not allow to obtain exactly the prescribed dose. Note that one drop of solution is equivalent to 1 mg of amitriptyline. In the treatment of a major depressive episode, the recommended dosage is:

• 50 mg per day in two doses which can be increased up to 150 mg per day in adults
• 10 to 25 mg per day may be increased to 100 mg twice daily in patients over 65 or those with cardiovascular disease

The effectiveness of the treatment is visible from 2 to 4 weeks. To avoid a possible relapse, it should be continued until 6 months after the disappearance of symptoms. To treat neuropathic pain or prevent migraines and tension headaches, the recommended dosage is different.
► In adults: a dose of 25 to 75 mg in the evening or in two daily doses. To improve treatment tolerance, a lower dose (3 to 25 mg) may be prescribed at the start of treatment and then gradually increased.
► In adults over 65 and patients with cardiovascular disease : a dose of 1 to 25 mg will be prescribed in the evening.
The action against pain generally appears after 2 to 4 weeks.
In the treatment of nocturnal enuresis, the recommended dosage is 10 to 20 mg in children from 6 to 10 years old, and 25 to 50 mg in children from 11 years old. For optimal effectiveness, the drug should be taken 60-90 minutes before bedtime.

What are the side effects of amitriptyline?

Amitriptyline-based drugs are very frequently responsible for drowsiness, tremors, dizziness, headache, speech disturbances, nausea, stuffy nose and weight gain. Due to the immediate sedative effect, increased vigilance is necessary in machine operators or machine users. Also, anticholinergic effects such as heart palpitations, blurred vision, constipation and dry mouth have been reported very frequently. Other side effects such as thirst, fatigue, erectile dysfunction or urination, heart damage and altered taste occur frequently. Due to the risk of occurrence of cardiac disorders, treatment requires vigilance in patients with bradycardia or unbalanced heart failure and in those taking a drug that prolongs the QT interval (visible on the electrocardiogram). In addition, before initiating amitriptyline medication in a child, an electrocardiogram should be performed in order to prevent cardiac risks.

Taking amitriptyline is prohibited in children under 6 years of age.

Are there any contraindications?

Contraindications of amitriptyline are:

• an allergy to one of the components
• severe liver disease
• a recent myocardial infarction
• heart rhythm disorders
• coronary heart disease

In addition, taking amitriptyline is prohibited in children under 6 years of age. On the other hand, this medicine is not contraindicated during pregnancy or during lactation.

Are there any risks of drug interactions?

Simultaneous intake of amitriptyline with an MAOI antidepressant (monoamine oxidase inhibitor) is strictly contraindicated. This combination can cause a serotonin syndrome which is defined by a life-threatening excess of serotonin in the brain. This syndrome manifests itself in particular by tremors, restlessness, sudden muscle twitching and increased body temperature. Similarly, it is strongly advised not to combine certain drugs with amitriptyline.

• tramadol, due to increased risk of seizures and serotonin syndrome.
• Antifungals (terbinafine, fluconazole) which increase the concentrations of amitriptyline and therefore its toxicity manifesting itself mainly by arrhythmias, urinary retention, convulsions or even respiratory depression.
• Medications that increase the QT interval visible on the electrocardiogram (antiarrhythmics, antihistamines, neuroleptics) due to an increased risk of serious cardiovascular effects.
• Diuretics such as furosemide which cause a potassium deficiency responsible for heart problems.
• Drugs potentially responsible for cardiovascular effects (general and local anaesthetics, nasal decongestants) which increase the risk of hypotension and arrhythmias. Patients treated with amitriptyline and taking one of these drugs should stop it several days before surgery and inform the anesthesiologist.
• Centrally acting antihypertensives (Catapressan®, Aldomet®) whose effect is canceled when combined with amitriptyline.
• Anticholinergic agents (certain nausea and vomiting medications: Mercalm®, Nausicalm®, medications for urinary incontinence, etc.) due to increased side effects such as constipation, urinary disorders and visual disturbances.

Source: Public Drug Database