Naratriptan (Naratriptanum)

Pharmacodynamics Pharmacokinetics Indications Carefully Contraindications Dosing and Administration Side effects
Read on
Clinical and pharmacological group: & nbsp

Neuroleptics

Serotonergic agents

Included in the formulation
АТХ:

N.02.C.C.02   Naratriptan

Pharmacodynamics:

The agonist of serotonin 5-HT1 receptors; antagonist of 5-HT1D receptors. Has a high affinity for the 5-HT1B / 1D receptors located in the intracranial blood vessels (in the brain and dura mater), inhibits the output of neurotransmitters and vasoactive neuropeptides by blocking 5-HT1D receptors.

Pharmacological effects: vasoconstrictive: it acts mainly on the intracranial blood vessels, especially on the carotid arteries, the effect occurs within 1 hour after ingestion and lasts for 24 hours, suppression of sensory activity of the trigeminal nerve (blockade of 5-HT1D receptors and suppression of neurotransmitter and neuropeptide release).

Pharmacokinetics:

Absorption is high, does not depend on food intake, slows down during a migraine attack. Absorption ~ 70% (63% in men, 74% in women), penetrates the blood-brain barrier. Relationship with plasma proteins 28-31%. The maximum concentration is achieved in 2-3 hours (3-4 hours during a migraine attack). Biotransformation in the liver with the participation of enzymes of the cytochrome P450 system with the formation of pharmacologically inactive metabolites. Half-life 6 h (in patients with renal insufficiency it increases by 80%, in patients with hepatic insufficiency it increases by 40%).Elimination by the kidneys is 80% (50% unchanged, 30% in the form of metabolites).

Indications:

Migraine with aura and without aura (relief of seizures), migraine status (as part of complex therapy).

ICD-10

VI.G40-G47.G43.1   Migraine with aura [classic migraine]

VI.G40-G47.G43.0   Migraine without aura [simple migraine]

VI.G40-G47.G43.9   Migraine, unspecified

VI.G40-G47.G43.8   Another migraine

VI.G40-G47.G43.3   Complicated migraine

VI.G40-G47.G43   Migraine

Contraindications:

Hypersensitivity, including sulfonamides, hemiplegic basilar or ophthalmoplegic migraine form, ischemic heart disease, myocardial infarction, cerebral circulation disorder, peripheral vascular disease (intermittent claudication syndrome), uncontrolled hypertension, renal failure of severe degree (creatinine clearance less than 15 ml / min), pregnancy, breast-feeding, adolescent (under 18 years) and advanced age.

Carefully:

Severe heart failure.

Pregnancy and lactation:

Category FDA C.

Qualitative and well-controlled studies on humans have not been conducted. In studies on rats and rabbits narrated in doses exceeding the recommended for humans at 11, 70 and 230 times,had a toxic effect on the fetus: caused an increase in mortality, perinatal pathology and developmental lag (partial or uneven ossification of the bones of the skull, sternum and ribs, additional ribs, variations in the development of large vessels, and a decrease in the increase in maternal weight during pregnancy).

There is no information on the penetration into human milk in humans. Penetrates into breast milk in rats. Contraindicated in breastfeeding.

Dosing and Administration:

Inside, during an attack, once 2.5 mg. When the symptoms of migraine recur - not again earlier than 4 hours. The maximum daily dose is 5 mg. For prevention of menstrual migraine - 2.5 mg 1 time per day for several days during or before the onset of menstruation.

Side effects:

Paresthesia, dizziness, drowsiness, weakness, sensation of pain, compression or compression in the throat and neck area, spasm of the coronary vessels, peripheral circulatory disorders, nausea, vomiting.

Overdose:

Increased blood pressure, dizziness, increased fatigue, impaired coordination of motion, pain and tension in the neck.

Treatment: maintenance of water-electrolyte balance, control of the function of external respiration, treatment of hypertension, if necessary consultation of a psychiatrist.With pain behind the breastbone or other signs of angina, an electrocardiogram must be removed.

Interaction:

When concomitant with naratriptanom ergotamine and its derivatives (including metesergid), other antimigraine drugs with a similar mechanism of action, the risk of side effects increases, as it is possible to change the pharmacokinetic parameters of naratriptan (combination is not recommended).

Strengthens the effect of sedatives.

Special instructions:

Do not use for the purpose of prevention.

With caution apply for mild or moderate failure of kidney or liver function, as well as in elderly patients (over 65 years of age).

Naratriptan should be used only if the diagnosis of migraine is undoubted.

When used to relieve a headache in a previously unidentified migraine or in patients with migraine, which occurs with atypical symptoms, other potentially serious neurological diseases should be ruled out.

Before starting to use it is necessary to exclude the presence of cardiovascular diseases in postmenopausal women, in men over the age of 40, in patients with risk factors for coronary heart disease.

Naratriptan contains a sulfonamide component, therefore, in patients with hypersensitivity to sulfonamides, it is theoretically possible to develop reactions of increased sensitivity to naratriptan.

Impact on the ability to drive vehicles and manage mechanisms

They are used with caution in patients whose activity requires an increased concentration of attention and a high rate of psychomotor reactions.

Instructions
Up