Naratriptan Pharmacology

Naratriptan

About Naratriptan
Antimigrain Drug, Selective Serotonin Agonist, Vasoconstricter Of Cranial Arteries
Mechanism of Action of Naratriptan
Three distinct pharmacological actions have been implicated in the antimigraine effect of the triptans: (1) stimulation of presynaptic 5-HT1D receptors, which serves to inhibit both dural vasodilation and inflammation; (2) direct inhibition of trigeminal nuclei cell excitability via 5-HT1B/1D receptor agonism in the brainstem and (3) vasoconstriction of meningeal, dural, cerebral or pial vessels as a result of vascular 5-HT1B receptor agonism.
Pharmacokinets of Naratriptan
Absorption: Well absorbed (74% oral biovaility). Peak plasma concentrations after 2-3 hr.
Distribution: Protein-binding: Approx 29%. Distributed into milk in rats.
Metabolism:Undergoes some hepatic metabolism by various cytochrome P450 isoenzymes.
Excretion: Primarily via urine (50% as unchanged drug, 30% as inactive metabolites).
Onset of Action for Naratriptan
30 minutes.
Duration of Action for Naratriptan
N/A
Half Life of Naratriptan
6 hr; markedly prolonged in renal or hepatic impairment
Side Effects of Naratriptan
1.Dizziness
2.Drowsiness
3.Malaise/fatigue
4.Nausea
5.Vomiting
6.Paraesthesia
7.Pain or pressure in throat or neck
8.Palpitation
9.Hypertension
10.ECG change
11.Hypotension
12.Heart murmurs
13.Bradycardia
14.Hyperlipidaemia
15.Hypercholesterolaemia
16.Hypothyroidism
17.Hyperglycaemia
18.Glycosuria
19.Ketonuria
20.Eye haemorrhage
21.Abnormal lfts
22.Abnormal bilirubin tests
23.Convulsions
24.Allergic reaction
25.Panic
26.Hallucinations
27.Dangerous: Coronary artery vasospasm, transient myocardial ischaemia, MI, ventricular tachycardia, ventricular fibrillation


Contra-indications of Naratriptan
1.Basilar/haemiplegic migraine
2.Uncontrolled hypertension
3.Ischaemic heart disease (angina, MI, silent ischaemia)
4.Coronary vasospasm
5.Peripheral vascular disease
6.Cerebrovascular syndromes (stroke, TIA)
7.Severe hepatic/renal impairment (crcl <15 ml/min)
Special Precautions while taking Naratriptan
1.Use only if there is a clear diagnosis of migraine
2.Exclude unrecognised coronary artery or CV disease before use in postmenopausal women, men >40 yr and those with risk factors for ischaemic heart disease
3.Not to be used prophylactically
4.Mild or moderate hepatic/renal impairment
5.May impair ability to drive or operate machinery
6.Hypersensitivity to sulfonamides
Pregnancy Related Information
Use with caution
Old Age Related Information
Not recommended
Breast Feeding Related Information
Use with caution
Children Related Information
Not recommended
Indications for Naratriptan
Acute migraine attacks
Interactions for Naratriptan
1.Increased levels/effects with oral contraceptives\
2.Dangerous: Increased risk of serotonin syndrome with serotonergic reuptake inhibitors (e.g. SSRIs/ serotonin noradrenaline reuptake inhibitors) and other serotonin agonists. Additive vasospastic effects with ergot-containing drugs.
Typical Dosage for Naratriptan
Adult: Initially, 1-2.5 mg at the onset of headache. If there is no response, do not take a 2nd dose. If headache returns after an initial response, dose may be repeated every 4 hr. Max: 5 mg in 24 hr
Renal impairment: Mild to moderate: Initiate at a lower dose. Max dose: 2.5 mg in 24 hr
Hepatic impairment: Mild to moderate: Initiate at a lower dose. Max dose: 2.5 mg in 24 hr

Schedule of Naratriptan
N/A
Storage Requirements for Naratriptan
Oral: Store at 20-25?C (68-77?F)

Effects of Missed Dosage of Naratriptan
N/A
Effects of Overdose of Naratriptan
Symptoms: Marked hypertension, lightheadedness, tension in the neck, tiredness, loss of coordination. Management: Supportive and symptomatic; no specific antidote. Continue monitoring for at least 24 hr or while symptoms or signs persist.

Home Delivery for Naratriptan in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including naratriptan.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for naratriptan and other medicines and health products. Home delivery services for naratriptan may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take naratriptan only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for naratriptan before they complete the sale. You can get this information while placing the order for naratriptan with the pharmacy.

Naratriptan is a generic medicine name and there are several brands available for it. Some of the brands for naratriptan might be better known than naratriptan itself. If the pharmacy that's willing to deliver medicines to your home doesn't have naratriptan in stock, you can ask for one of the branded alternatives for naratriptan.