Imitrex Injection

/ GSK

Sumatriptan injection should not be used prophylactically. The recommended dose of Sumatriptan should not be exceeded. It is recommended to start the treatment at the first sign of a migraine headache or associated symptoms such as nausea, vomiting or photophobia. It is equally effective at whatever stage of the attack it is administered.
The efficacy of sumatriptan is independent of the duration of the attack when starting treatment. Administration during a migraine aura prior to other symptoms occurring may not prevent the development of a headache. Sumatriptan Injection should be injected subcutaneously using an auto-injector. Patients should be advised to observe strictly the instruction leaflet for the Sumatriptan auto-injector especially regarding the safe disposal of syringes and needles.
Migraine: Adult: The recommended adult dose of Sumatriptan is a single 6 mg subcutaneous injection.  If a patient does not respond to the first dose of sumatriptan, a second dose should not be taken for the same attack. In these cases the attack can be treated with paracetamol, acetylsalicylic acid, or non-steroidal anti-inflammatory drugs. Sumatriptan injection may be taken for subsequent attacks. If the patient has responded to the first dose, but the symptoms recur a second dose may be given in the next 24 hours, provided that there is a minimum interval of 1 hour between the two doses. The maximum dose in 24 hours is two 6 mg injections (12 mg). Sumatriptan is recommended as monotherapy for the acute treatment of migraine and should not be given concomitantly with ergotamine or derivatives of ergotamine (including methysergide).
Cluster headache: Adult: The recommended adult dose is a single 6mg subcutaneous injection for each cluster attack. The maximum dose in 24 hours is two 6mg injections (12mg) with a minimum interval of one hour between the two doses.
Children and Adolescents (under 18 years of age): Sumatriptan Injection is not recommended for use in children and adolescents due to insufficient data on safety and efficacy.
Older people (over 65): Experience of the use of Sumatriptan Injection in patients aged over 65 years is limited. The pharmacokinetics do not differ significantly from a younger population, but, until further clinical data are available, the use of Sumatriptan in patients aged over 65 years is not recommended.
See prescribing information for full details.

Acute relief of migraine attacks with or without aure, cluster headache. For the acute treatment of migraine attacks associated with women’s menstrual cycle.

Hypersensitivity to sumatriptan or to any of the excipients. Sumatriptan should not be given to patients who have had myocardial infarction or have ischaemic heart disease, coronary vasospasm (Prinzmetal’s angina), peripheral vascular disease or patients who have symptoms or signs consistent with ischaemic heart disease. Sumatriptan should not be administered to patients with a history of cerebovascular accident (CVA) or transient ischaemic attack (TIA).
Sumatriptan should not be administered to patients with severe hepatic impairment. he use of sumatriptan in patients with moderate and severe hypertension and mild uncontrolled hypertension is contraindicated.
The concomitant administration of ergotamine or derivatives of ergotamine (including methysergide) or any triptan/5-hydroxytryptamine1 (5-HT1) receptor agonist with sumatriptan is contraindicated. Concurrent administration of monoamine oxidase inhibitors and sumatriptan is contraindicated. Sumatriptan Injection must not be used within two weeks of discontinuation of therapy with monoamine oxidase inhibitors.       

Warnings: Sumatriptan should only be used where there is a clear diagnosis of migraine or cluster headache. Sumatriptan is not indicated for use in the management of hemiplegic, basilar or opthalmoplegic migraine.
Sumatriptan Injection should not be given intravenously because of its potential to cause vasospasm. The vasospasm may result in arrhythmias, ischaemic ECG changes or myocardial infarction. Before treating headaches in patients not previously diagnosed as migraineurs, and in migraineurs who present with atypical symptoms, care should be taken to exclude other potentially serious neurological conditions. It should be noted that migraineurs may be at risk of certain cerebrovascular events (e.g. cerebrovascular accident, transient ischaemic attack).
Following administration, sumatriptan can be associated with transient symptoms including chest pain and tightness which may be intense and involve the throat. Where such symptoms are thought to indicate ischaemic heart disease, no further doses of sumatriptan should be given and appropriate evaluation should be carried out. Sumatriptan should not be given to patients with risk factors for ischaemic heart disease, including those patients who are heavy smokers or users of nicotine substitution therapies, without prior cardiovascular evaluation. Special consideration should be given to postmenopausal women and males over 40 with these risk factors. These evaluations however, may not identify every patient who has cardiac disease and, in very rare cases, serious cardiac events have occurred in patients without underlying cardiovascular disease.
If the patient experiences symptoms which are severe or persistent or are consistent with angina, further doses should not be taken until appropriate investigations have been carried out to check for the possibility of ischaemic changes.
Sumatriptan should be administered with caution to patients with mild controlled hypertension, since transient increases in blood pressure and peripheral vascular resistance have been observed in a small proportion of patients.
There have been rare post-marketing reports describing patients with serotonin syndrome (including altered mental status, autonomic instability and neuromuscular abnormalities) following the use of a selective serotonin reuptake inhibitor (SSRI) and sumatriptan. Serotonin syndrome has been reported following concomitant treatment with triptans and serotonin noradrenaline reuptake inhibitors (SNRIs) and triptan with tricyclic antidepressants (TCAs). If concomitant treatment with sumatriptan and an SSRI/SNRI is clinically warranted, appropriate observation of the patient is advised.
Sumatriptan should be administered with caution to patients with conditions which may affect significantly the absorption, metabolism or excretion of the drug e.g. impaired hepatic (Child Pugh grade A or B) or renal function. Sumatriptan should be used with caution in patients with a history of seizures or other risk factors which lower the seizure threshold, as seizures have been reported in association with sumatriptan Patients with known hypersensitivity to sulphonamides may exhibit an allergic reaction following administration of Sumatriptan. Reactions may range from cutaneous hypersensitivity to anaphylaxis. Evidence of cross-sensitivity is limited, however, caution should be exercised before using sumatriptan in these patients. Undesirable effects may be more common during concomitant use of triptans and herbal preparations containing St John’s Wort (Hypericum perforatum). Prolonged use of any type of painkiller for headaches can make them worse. If this situation is experienced or suspected, medical advice should be obtained and treatment should be discontinued. The diagnosis of medication overuse headache (MOH) should be suspected in patients who have frequent or daily headaches despite (or because of) the regular use of headache medications. Reports of transient and permanent blindness and significant partial vision loss have been reported with the use of 5-HT1 agonists. Since visual disorders may be part of a migraine attack, a causal relationship between these events and the use of 5-HT1 agonists have not been clearly established.

Nervous System Disorders: Common: Dizziness, drowsiness, sensory disturbance including paraesthesia and hypoaesthesia.
Vascular Disorders: Common: Transient increases in blood pressure arising soon after treatment. Flushing.
Respiratory, Thoracic and Mediastinal Disorders: Common: Dyspnoea.
Gastrointestinal Disorders: Common: Nausea and vomiting occurred in some patients but it is unclear if this is related to sumatriptan or the underlying condition.
Musculoskeletal and Connective Tissue Disorders: Common: Sensations of heaviness (usually transient and may be intense and can affect any part of the body including the chest and throat). Myalgia.
General Disorders and Administration Site Conditions: Very common: Transient injection site pain. Injection site stinging/burning, swelling, erythema, bruising and bleeding have also been reported.
Common: Pain, sensations of heat or cold, pressure or tightness (these events are usually transient and may be intense and can affect any part of the body including the chest and throat).  Feelings of weakness, fatigue (both events are mostly mild to moderate in intensity and transient). Although direct comparisons are not available, flushing, paraesthesia and sensations of heat, pressure, and heaviness may be more common after sumatriptan injection.  Conversely, nausea, vomiting and fatigue appear to be less frequent with subcutaneous administration of sumatriptan injection than with tablets.
See prescribing information for full details.

Studies in healthy subjects show that Sumatriptan does not interact with propranolol, flunarizine, pizotifen or alcohol. There are limited data on an interaction with preparations containing ergotamine or another triptan/5-HT1 receptor agonist. The increased risk of coronary vasospasm is a theoretical possibility and concomitant administration is contraindicated The period of time that should elapse between the use of sumatriptan and ergotamine-containing preparations or another triptan/5-HT1 receptor agonist is not known. This will also depend on the doses and types of products used. The effects may be additive. It is advised to wait at least 24 hours following the use of ergotamine-containing preparations or another triptan/5-HT1 receptor agonist before administering sumatriptan. Conversely, it is advised to wait at least 6 hours following use of sumatriptan before administering an ergotamine-containing product and at least 24 hours before administering another triptan/5-HT1 receptor agonist.
An interaction may occur between sumatriptan and MAOIs and concomitant administration is contraindicated. There have been rare post-marketing reports describing patients with serotonin syndrome (including altered mental status, autonomic instability and neuromuscular abnormalities) following the use of SSRIs and sumatriptan. Serotonin syndrome has also been reported following concomitant treatment with triptans and SNRIs and triptan with tricyclic antidepressants (TCAs).
See prescribing information for full details.

Pregnancy: Post-marketing data from the use of sumatriptan during the first trimester in over 1,000 women are available. Although these data contain insufficient information to draw definitive conclusions, they do not point to an increased risk of congenital defects. Experience with the use of sumatriptan in the second and third trimester is limited. Administration of sumatriptan should only be considered if the expected benefit to the mother is greater than any possible risk to the foetus.
Lactation: It has been demonstrated that following subcutaneous administration sumatriptan is excreted into breast milk. Infant exposure can be minimised by avoiding breast feeding for 12 hours after treatment, during which time any breast milk expressed should be discarded.
See prescribing information for full details.   

There have been some reports of overdose with Sumatriptan Injection. Patients have received single injections of up to 12 mg subcutaneously without significant adverse effects. Doses in excess of 16 mg subcutaneously were not associated with side effects other than those mentioned. If overdose with Sumatriptan occurs, the patient should be monitored for at least ten hours and standard supportive treatment applied as required. It is unknown what effect haemodialysis or peritoneal dialysis has on the plasma concentrations of Sumatript.
See prescribing information for full details.

Effects on ability to drive and use machines: No studies on the effects on the ability to drive and use machines have been performed. Drowsiness may occur as a result of migraine or treatment with Sumatriptan. This may influence the ability to drive and to operate machinery.
Storage: Do not store above 30°C. Sumatriptan Injection should be protected from light.