sumatriptan succinate

Action

Selectively activates vascular 5-HT₁ receptor sites, causing vasoconstriction in intracranial arteries

Availability

Injection: 6 mg/0.5-ml prefilled syringes, 0.6 mg/0.5-ml single-dose vials; 6 mg/0.5-ml prefilled, single-dose, needle-free subcutaneous delivery system; 4- and 6-mg STATdose system containing two prefilled single-dose syringe cartridges and one STATdose Pen; 4-and 6-mg kits containing two prefilled single-dose syringe cartridges and one autoinjector pen

Nasal spray: 5 mg in 100-mcl unit dose spray device (package of six), 20 mg in 100-mcl unit dose spray device (package of six)

Tablets: 25 mg, 50 mg, 100 mg

Indications and dosages

➣ Acute migraine, cluster headaches

Adults: Initially, 25 mg P.O.; if response inadequate after 2 hours, may give up to 100 mg P.O. If migraine recurs, repeat dose q 2 hours, not to exceed 200 mg/day. Or 6 mg subcutaneously, repeated as needed after 1 hour, not to exceed 12 mg in 24 hours. If P.O. therapy will follow subcutaneous injection, additional P.O. sumatriptan may be given q 2 hours, not to exceed 100 mg/day. Or a single dose of 5, 10, or 20 mg intranasally in one nostril, repeated p.r.n. in 2 hours, not to exceed 40 mg in 24 hours.

Dosage adjustment

• Hepatic impairment

Contraindications

• Hypersensitivity to drug

• Hemiplegic or basilar migraine headache

• Ischemic cardiac, cerebrovascular, or peripheral vascular disease (such as a history of myocardial infarction, stroke, angina, or ischemic bowel)

• Uncontrolled hypertension

• Severe hepatic impairment

• MAO inhibitor use within past 14 days

• Use of other 5-HT₁ agonists, ergotamine-containing drugs, or ergot-type products within past 24 hours

Precautions

Use cautiously in:

• patients with cardiovascular risk factors (hypertension, hypercholesterolemia, smoking, obesity, diabetes, family history of cardiovascular disease, men over age 40, menopausal women)

• elderly patients

• women of childbearing age

• pregnant or breastfeeding patients

• children younger than age 18 (safety not established).

Administration

• Be aware that parenteral form is for subcutaneous use only.

• Be aware that an autoinjection device is available for use with the 4- and 6-mg prefilled syringe cartridges to facilitate patient self-administration using the 4- or 6-mg dose. For patients receiving doses other than 4 or 6 mg, only the 6-mg single-dose vial dosage form should be used.

See If patient has risk factors for coronary artery disease, know that first dose should be given in medical setting with emergency equipment at hand.

See Don't give within 14 days of MAO inhibitors.

See Don't administer within 24 hours of other 5-HT₁ agonists, ergotamine-containing drugs, or ergot-type products.

Adverse reactions

CNS: headache, malaise, dizziness, drowsiness, fatigue, vertigo, anxiety, tight feeling in head, numbness

CV: angina, chest pressure or tightness, transient hypertension, ECG changes, coronary vasospasm, myocardial infarction

EENT: vision changes, nasal sinus discomfort, throat discomfort

GI: abdominal discomfort, dysphagia

Musculoskeletal: jaw discomfort, muscle cramps, myalgia, neck pain or stiffness

Skin: flushing; tingling; warm, cool or, burning sensation

Other: injection site reaction, feeling of heaviness or tightness

Interactions

Drug-drug. Dihydroergotamine, ergotamine, methysergide: increased risk of vasospastic reaction

Lithium, MAO inhibitors, selective serotonin reuptake inhibitors: weakness, hyperreflexia, incoordination

Drug-herbs. Horehound: enhanced serotonergic effects

Patient monitoring

See Monitor cardiovascular status closely. Be aware that drug may cause serious and possibly fatal cardiac disorders.

• Watch for neurologic and vision changes. Institute safety measures as needed to prevent injury.

• Monitor patient's response to drug. Assess need for repeat doses.

• Watch for injection site reaction, which should subside within 1 hour.

Patient teaching

• Instruct patient to take as soon as possible after migraine onset.

See Teach patient to recognize and immediately report serious cardiovascular reactions.

• Explain proper drug use. Tell patient it doesn't prevent migraine.

• With subcutaneous use, instruct patient to follow directions in the patient leaflet carefully before injecting drug and to inject dose subcutaneously using spring-loaded injector system or needle-free subcutaneous delivery system included in package. If headache recurs after dose, tell him he may take a second dose, but should wait at least 1 hour after initial dose and shouldn't exceed two 6-mg injections in a 24-hour period. Instruct him to report injection site reaction that doesn't subside within 1 hour.

• With oral use, tell patient he may take a second dose 2 hours after first dose if migraine recurs. Tell him he may repeat oral doses every 2 hours as needed, up to 200 mg in a 24-hour period.

• With intranasal use, tell patient to spray 5, 10, or 20 mg into one nostril, as prescribed. Tell him he may repeat dose after 2 hours but shouldn't exceed 40 mg in a 24-hour period.

• Advise patient not to use drug for more than four episodes per month.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and herbs mentioned above.