IMITREX
Available from Value Pharmaceuticals at discount price
1. Administration Route - Oral 
CONTRAINDICATIONS 
  
Sumatriptan succinate tablets should not be given to patients with history, symptoms, or signs of 
ischemic cardiac, cerebrovascular, or peripheral vascular syndromes. In addition, patients with other 
significant underlying cardiovascular diseases should not receive sumatriptan succinate tablets. 
Ischemic cardiac syndromes include, but are not limited to, angina pectoris of any type (e.g., stable 
angina of effort and vasospastic forms of angina such as the Prinzmetal variant), all forms of 
myocardial infarction, and silent myocardial ischemia. Cerebrovascular syndromes include, but are 
not limited to, strokes of any type as well as transient ischemic attacks. Peripheral vascular disease 
includes, but is not limited to, ischemic bowel disease (see WARNINGS). 
  
Because sumatriptan succinate tablets may increase blood pressure, they should not be given to 
patients with uncontrolled hypertension. 
  
Concurrent administration of MAO-A inhibitors or use within 2 weeks of discontinuation of 
MAO-A inhibitor therapy is contraindicated (see CLINICAL PHARMACOLOGY, Drug 
Interactions and DRUG INTERACTIONS). 
  
Sumatriptan succinate tablets should not be administered to patients with hemiplegic or basilar 
migraine. 
  
Sumatriptan succinate tablets and any ergotamine-containing or ergot-type medication (like 
dihydroergotamine or methysergide) should not be used within 24 hours of each other, nor should 
sumatriptan succinate and another 5-HT1 agonist. 
  
Sumatriptan succinate tablets are contraindicated in patients with hypersensitivity to sumatriptan or 
any of their components. 
  
Sumatriptan succinate tablets are contraindicated in patients with severe hepatic impairment. 
  
WARNINGS 
  
Sumatriptan succinate tablets should only be used where a clear diagnosis of migraine headache has 
been established. 
  
Risk of Myocardial Ischemia and/or Infarction and Other Adverse Cardiac 
Events: Sumatriptan should not be given to patients with documented ischemic or vasospastic 
coronary artery disease (CAD) (see CONTRAINDICATIONS). It is strongly recommended that 
sumatriptan not be given to patients in whom unrecognized CAD is predicted by the presence of 
risk factors (e.g., hypertension, hypercholesterolemia, smoker, obesity, diabetes, strong family 
history of CAD, female with surgical or physiological menopause, or male over 40 years of age) 
unless a cardiovascular evaluation provides satisfactory clinical evidence that the patient is 
reasonably free of coronary artery and ischemic myocardial disease or other significant underlying 
cardiovascular disease. The sensitivity of cardiac diagnostic procedures to detect cardiovascular 
disease or predisposition to coronary artery vasospasm is modest, at best. If, during the 
cardiovascular evaluation, the patient's medical history or electrocardiographic investigations reveal 
findings indicative of, or consistent with, coronary artery vasospasm or myocardial ischemia, 
sumatriptan should not be administered (see CONTRAINDICATIONS). 
  
For patients with risk factors predictive of CAD, who are determined to have a satisfactory 
cardiovascular evaluation, it is strongly recommended that administration of the first dose of 
sumatriptan take place in the setting of a physician's office or similar medically staffed and equipped 
facility unless the patient has previously received sumatriptan. Because cardiac ischemia can occur 
in the absence of clinical symptoms, consideration should be given to obtaining on the first occasion 
of use an electrocardiogram (ECG) during the interval immediately following sumatriptan succinate 
tablets, in these patients with risk factors. 
  
It is recommended that patients who are intermittent long-term users of sumatriptan and who have 
or acquire risk factors predictive of CAD, as described above, undergo periodic interval 
cardiovascular evaluation as they continue to use sumatriptan. 
  
The systematic approach described above is intended to reduce the likelihood that patients with 
unrecognized cardiovascular disease will be inadvertently exposed to sumatriptan. 
  
Drug-Associated Cardiac Events and Fatalities: Serious adverse cardiac events, including acute 
myocardial infarction, life-threatening disturbances of cardiac rhythm, and death have been reported 
within a few hours following the administration of sumatriptan succinate injection or sumatriptan 
succinate tablets. Considering the extent of use of sumatriptan in patients with migraine, the 
incidence of these events is extremely low. 
  
The fact that sumatriptan can cause coronary vasospasm, that some of these events have occurred 
in patients with no prior cardiac disease history and with documented absence of CAD, and the 
close proximity of the events to sumatriptan use support the conclusion that some of these cases 
were caused by the drug. In many cases, however, where there has been known underlying 
coronary artery disease, the relationship is uncertain. 
  
Premarketing Experience with Sumatriptan: Of 6348 patients with migraine who participated in 
premarketing controlled and uncontrolled clinical trials of oral sumatriptan, two experienced clinical 
adverse events shortly after receiving oral sumatriptan that may have reflected coronary 
vasospasm. Neither of these adverse events was associated with a serious clinical outcome. 
  
Among the more than 1900 patients with migraine who participated in premarketing controlled 
clinical trials of subcutaneous sumatriptan, there were 8 patients who sustained clinical events 
during or shortly after receiving sumatriptan that may have reflected coronary artery vasospasm. 
Six of these 8 patients had ECG changes consistent with transient ischemia, but without 
accompanying clinical symptoms or signs. Of these 8 patients, 4 had either findings suggestive of 
CAD or risk factors predictive of CAD prior to study enrollment. 
  
Among approximately 4000 patients with migraine who participated in premarketing controlled and 
uncontrolled clinical trials of sumatriptan nasal spray, one patient experienced an asymptomatic 
subendocardial infarction possibly subsequent to a coronary vasospastic event. 
  
Postmarketing Experience with Sumatriptan: Serious cardiovascular events, some resulting in 
death, have been reported in association with the use of sumatriptan succinate injection or tablets. 
The uncontrolled nature of postmarketing surveillance, however, makes it impossible to determine 
definitively the proportion of the reported cases that were actually caused by sumatriptan or to 
reliably assess causation in individual cases. On clinical grounds, the longer the latency between the 
administration of sumatriptan succinate and the onset of the clinical event, the less likely the 
association is to be causative. Accordingly, interest has focused on events beginning within 1 hour 
of the administration of sumatriptan succinate. 
  
Cardiac events that have been observed to have onset within 1 hour of sumatriptan administration 
include: coronary artery vasospasm, transient ischemia, myocardial infarction, ventricular 
tachycardia and ventricular fibrillation, cardiac arrest, and death. 
  
Some of these events occurred in patients who had no findings of CAD and appear to represent 
consequences of coronary artery vasospasm. However, among domestic reports of serious cardiac 
events within 1 hour of sumatriptan administration, almost all of the patients had risk factors 
predictive of CAD and the presence of significant underlying CAD was established in most cases 
(see CONTRAINDICATIONS). 
  
Drug-Associated Cerebrovascular Events and Fatalities: Cerebral hemorrhage, subarachnoid 
hemorrhage, stroke, and other cerebrovascular events have been reported in patients treated with 
oral or subcutaneous sumatriptan, and some have resulted in fatalities. The relationship of 
sumatriptan to these events is uncertain. In a number of cases, it appears possible that the 
cerebrovascular events were primary, sumatriptan having been administered in the incorrect belief 
that the symptoms experienced were a consequence of migraine when they were not. As with 
other acute migraine therapies, 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 also be noted that patients with 
migraine may be at increased risk of certain cerebrovascular events (e.g., cerebrovascular 
accident, transient ischemic attack). 
  
Other Vasospasm-Related Events: Sumatriptan may cause vasospastic reactions other than 
coronary artery vasospasm. Both peripheral vascular ischemia and colonic ischemia with abdominal 
pain and bloody diarrhea have been reported. 
  
Increase in Blood Pressure: Significant elevation in blood pressure, including hypertensive crisis, 
has been reported on rare occasions in patients with and without a history of hypertension. 
Sumatriptan is contraindicated in patients with uncontrolled hypertension (see 
CONTRAINDICATIONS). Sumatriptan should be administered with caution to patients with 
controlled hypertension as transient increases in blood pressure and peripheral vascular resistance 
have been observed in a small proportion of patients. 
  
Concomitant Drug Use: In patients taking MAO-A inhibitors, sumatriptan plasma levels attained 
after treatment with recommended doses are sevenfold higher following oral administration than 
those obtained under other conditions. Accordingly, the coadministration of sumatriptan succinate 
tablets and an MAO-A inhibitor is contraindicated (see CLINICAL PHARMACOLOGY and 
CONTRAINDICATIONS). 
  
Hypersensitivity: Hypersensitivity (anaphylaxis/anaphylactoid) reactions have occurred on rare 
occasions in patients receiving sumatriptan. Such reactions can be life threatening or fatal. In 
general, hypersensitivity reactions to drugs are more likely to occur in individuals with a history of 
sensitivity to multiple allergens (see CONTRAINDICATIONS). 
  
PRECAUTIONS 
  
General 
  
Chest discomfort and jaw or neck tightness have been reported following use of sumatriptan 
succinate tablets and have also been reported infrequently following administration of sumatriptan 
nasal spray. Chest, jaw, or neck tightness is relatively common after administration of sumatriptan 
succinate injection. Only rarely have these symptoms been associated with ischemic ECG changes. 
However, because sumatriptan may cause coronary artery vasospasm, patients who experience 
signs or symptoms suggestive of angina following sumatriptan should be evaluated for the presence 
of CAD or a predisposition to Prinzmetal's variant angina before receiving additional doses of 
sumatriptan, and should be monitored electrocardiographically if dosing is resumed and similar 
symptoms recur. Similarly, patients who experience other symptoms or signs suggestive of 
decreased arterial flow, such as ischemic bowel syndrome or Raynaud's syndrome following 
sumatriptan should be evaluated for atherosclerosis or predisposition to vasospasm (see 
WARNINGS). 
  
Sumatriptan succinate should also be administered with caution to patients with diseases that may 
alter the absorption, metabolism, or excretion of drugs, such as impaired hepatic or renal function. 
  
There have been rare reports of seizure following administration of sumatriptan. Sumatriptan should 
be used with caution in patients with a history of epilepsy or structural brain lesions that lower their 
seizure threshold. 
  
Care should be taken to exclude other potentially serious neurologic conditions before treating 
headache in patients not previously diagnosed with migraine headache or who experience a 
headache that is atypical for them. There have been rare reports where patients received 
sumatriptan for severe headaches that were subsequently shown to have been secondary to an 
evolving neurologic lesion (see WARNINGS). 
  
For a given attack, if a patient does not respond to the first dose of sumatriptan, the diagnosis of 
migraine should be reconsidered before administration of a second dose. 
  
Binding to Melanin-Containing Tissues: In rats treated with a single subcutaneous dose (0.5 
mg/kg) or oral dose (2 mg/kg) of radiolabeled sumatriptan, the elimination half-life of radioactivity 
from the eye was 15 and 23 days, respectively, suggesting that sumatriptan and/or its metabolites 
bind to the melanin of the eye. Because there could be accumulation in melanin-rich tissues over 
time, this raises the possibility that sumatriptan could cause toxicity in these tissues after extended 
use. However, no effects on the retina related to treatment with sumatriptan were noted in any of 
the oral or subcutaneous toxicity studies. Although no systematic monitoring of ophthalmologic 
function was undertaken in clinical trials, and no specific recommendations for ophthalmologic 
monitoring are offered, prescribers should be aware of the possibility of long-term ophthalmologic 
effects. 
  
Corneal Opacities: Sumatriptan causes corneal opacities and defects in the corneal epithelium in 
dogs; this raises the possibility that these changes may occur in humans. While patients were not 
systematically evaluated for these changes in clinical trials, and no specific recommendations for 
monitoring are being offered, prescribers should be aware of the possibility of these changes (See 
ANIMAL PHARMACOLOGY). 
  
Information for the Patient 
  
See PATIENT PACKAGE INSERT at the end of the Intranasal product information for additional 
information for patients. 
  
Laboratory Tests 
  
No specific laboratory tests are recommended for monitoring patients prior to and/or after treatment 
with sumatriptan. 
  
Drug/Laboratory Test Interactions 
  
Sumatriptan succinate tablets are not known to interfere with commonly employed clinical 
laboratory tests. 
  
Carcinogenesis, Mutagenesis, and Impairment of Fertility 
  
Carcinogenesis: In carcinogenicity studies, rats and mice were given sumatriptan by oral gavage 
(rats: 104 weeks), or drinking water (mice: 78 weeks). Average exposures achieved in mice 
receiving the highest dose (target dose of 160 mg/kg per day) were approximately 40 times the 
exposure attained in humans after the maximum recommended single oral dose of 100 mg. The 
highest dose administered to rats (160 mg/kg per day, reduced from 360 mg/kg per day during week 
21) was approximately 15 times the maximum recommended single human dose of 100 mg on a 
mg/m2 basis. There was no evidence of an increase in tumors in either species related to 
sumatriptan administration. 
  
Mutagenesis: Sumatriptan was not mutagenic in the presence or absence of metabolic activation 
when tested in two gene mutation assays (the Ames test and the in vitro mammalian Chinese 
hamster V79/HGPRT assay). In two cytogenetics assays (the in vitro human lymphocyte assay 
and the in vivo rat micronucleus assay) sumatriptan was not associated with clastogenic activity. 
  
Impairment of Fertility: In a study in which male and female rats were dosed daily with oral 
sumatriptan prior to and throughout the mating period, there was a treatment-related decrease in 
fertility secondary to a decrease in mating in animals treated with 50 and 500 mg/kg per day. The 
highest no-effect dose for this finding was 5 mg/kg a day, or approximately one-half of the 
maximum recommended single human oral dose of 100 mg on a mg/m2 basis. It is not clear 
whether the problem is associated with treatment of the males or females or both combined. In a 
similar study by the subcutaneous route there was no evidence of impaired fertility at 60 mg/kg per 
day, the maximum dose tested, which is equivalent to approximately 6 times the maximum 
recommended single human oral dose of 100 mg on a mg/m2 basis. 
  
Pregnancy Category C 
  
In reproductive toxicity studies in rats and rabbits, oral treatment with sumatriptan was associated 
with embroylethality, fetal abnormalities, and pup mortality. When administered by the intravenous 
route to rabbits, sumatriptan has been shown to be embryolethal. There are no adequate and 
well-controlled studies in pregnant women. Therefore, sumatriptan succinate tablets should be used 
during pregnancy only if the potential benefit justifies the potential risk to the fetus. In assessing this 
information, the following findings should be considered. 
  
Embryolethality: When given orally or intravenously to pregnant rabbits daily throughout the period 
of organogenesis, sumatriptan caused embryolethality at doses at or close to those producing 
maternal toxicity. In the oral studies this dose was 100 mg/kg per day and in the intravenous studies 
this dose was 2.0 mg/kg per day. The mechanism of the embryolethality is not known. The highest 
no-effect dose for embryolethality by the oral route was 50 mg/kg per day, which is approximately 9 
times the maximum single recommended human oral dose of 100 mg on a mg/m2 basis. By the 
intravenous route, the highest no-effect dose was 0.75 mg/kg per day, or approximately one-tenth of 
the maximum single recommended human oral dose of 100 mg on a mg/m2 basis. 
  
The intravenous administration of sumatriptan to pregnant rats throughout organogenesis at 12.5 
mg/kg per day, the maximum dose tested, did not cause embryolethality. This dose is equivalent to 
the maximum single recommended human oral dose of 100 mg on a mg/m2 basis. Additionally, in a 
study in rats given subcutaneous sumatriptan daily, prior to and throughout pregnancy at 60 mg/kg 
per day, the maximum dose tested, there was no evidence of increased embryo/fetal lethality. This 
dose is equivalent to approximately 6 times the maximum recommended single human oral dose of 
100 mg on a mg/m2 basis. 
  
Teratogenicity: Oral treatment of pregnant rats with sumatriptan during the period of 
organogenesis resulted in an increased incidence of blood vessel abnormalities (cervicothoracic and 
umbilical) at doses of approximately 250 mg/kg per day or higher. The highest no-effect dose was 
approximately 60 mg/kg per day, which is approximately 6 times the maximum single recommended 
human oral dose of 100 mg on a mg/m2 basis. Oral treatment of pregnant rabbits with sumatriptan 
during the period of organogenesis resulted in an increased incidence of cervicothoracic vascular 
and skeletal abnormalities. The highest no-effect dose for these effects was 15 mg/kg per day, or 
approximately 3 times the maximum single recommended human oral dose of 100 mg on a mg/m2 
basis. 
  
A study in which rats were dosed daily with oral sumatriptan prior to and throughout gestation 
demonstrated embryo/fetal toxicity (decreased body weight, decreased ossification, increased 
incidence of rib variations) and an increased incidence of a syndrome of malformations (short 
tail/short body and vertebral disorganization) at 500 mg/kg per day. The highest no-effect dose was 
50 mg/kg per day, or approximately 5 times the maximum single recommended human oral dose of 
100 mg on a mg/m2 basis. In a study in rats dosed daily with subcutaneous sumatriptan prior to and 
throughout pregnancy, at a dose of 60 mg/kg per day, the maximum dose tested, there was no 
evidence of teratogenicity. This dose is equivalent to approximately 6 times the maximum 
recommended single human oral dose of 100 mg on a mg/m2 basis. 
  
Pup Deaths: Oral treatment of pregnant rats with sumatriptan during the period of organogenesis 
resulted in a decrease in pup survival between birth and postnatal day 4 at doses of approximately 
250 mg/kg per day or higher. The highest no-effect dose for this effect was approximately 60 
mg/kg per day, or 6 times the maximum single recommended human oral dose of 100 mg on a 
mg/m2 basis. 
  
Oral treatment of pregnant rats with sumatriptan from gestational day 17 through postnatal day 21 
demonstrated a decrease in pup survival measured at postnatal days 2, 4, and 20 at the dose of 1000 
mg/kg per day. The highest no-effect dose for this finding was 100 mg/kg per day, approximately 10 
times the maximum single recommended human oral dose of 100 mg on a mg/m2 basis. In a similar 
study in rats by the subcutaneous route there was no increase in pup death at 81 mg/kg per day, the 
highest dose tested, which is equivalent to 8 times the maximum single recommended human oral 
dose of 100 mg/m2 basis. 
  
To monitor fetal outcomes of pregnant women exposed to sumatriptan succinate, Glaxo Wellcome 
Inc. maintains a Sumatriptan Pregnancy Registry. Physicians are encouraged to register patients by 
calling (800) 336–2176. 
  
Nursing Mothers 
  
Sumatriptan is excreted in human breast milk. Therefore, caution should be exercised when 
considering the administration of sumatriptan succinate tablets to a nursing woman. 
  
Pediatric Use 
  
Safety and effectiveness of sumatriptan succinate tablets in pediatric patients have not been 
established. 
  
Completed placebo-controlled clinical trials evaluating oral sumatriptan (25 to 100 mg) in pediatric 
patients aged 12 to 17 years have enrolled a total of 701 adolescent migraineurs. These studies did 
not establish the efficacy of oral sumatriptan compared to placebo in the treatment of migraine in 
adolescents. Adverse events observed in these clinical trials were similar in nature to those reported 
in clinical trials in adults. The frequency of all adverse events in these patients appeared to be both 
dose- and age-dependent, with younger patients reporting events more commonly than older 
adolescents. Postmarketing experience includes a limited number of reports that describe pediatric 
patients who have experienced adverse events, some clinically serious, after use of subcutaneous 
sumatriptan and/or oral sumatriptan. These reports include events similar in nature to those reported 
rarely in adults. A myocardial infarct has been reported in a 14-year old male following the use of 
oral sumatriptan; clinical signs occurred within 1 day of drug administration. Since clinical data to 
determine the frequency of serious adverse events in pediatric patients who might receive 
injectable, oral, or intranasal sumatriptan are not presently available, the use of sumatriptan in 
patients aged younger than 18 years is not recommended. 
  
Geriatric Use 
  
The use of sumatriptan in elderly patients is not recommended because elderly patients are more 
likely to have decreased hepatic function, they are at higher risk for CAD, and blood pressure 
increases may be more pronounced in the elderly (see WARNINGS).
  
2. Administration Route – subcutaneous 
CONTRAINDICATIONS 
  
Sumatriptan succinate injection should not be given intravenously because of its potential to cause 
coronary vasospas. 
  
Because sumatriptan succinate injection may increase blood pressure, it should not be given to 
patients with uncontrolled hypertension. 
  
Sumatriptan succinate injection and any ergotamine-containing or ergot-type medication (like 
dihydroergotamine or methysergide) should not be used within 24 hours of each other, nor should 
sumatriptan succinate and another 5–HT1 agonist. 
  
Sumatriptan succinate injection should not be administered to patients with hemiplegic or basilar 
migraine. 
  
Sumatriptan succinate injection is contraindicated in patients with hypersensitivity to sumatriptan or 
any of its components. 
  
Sumatriptan succinate injection is contraindicated in patients with patients with severe hepatic 
impairment. 
  
WARNINGS 
  
Sumatriptan succinate injection should only be used where a clear diagnosis migraine or cluster 
headache has been established. The prescriber should be aware that cluster headache patients 
often possess one or more predictive risk factors for coronary artery disease (CAD). 
  
Risk of Myocardial Ischemia and/or Infarction and Other Adverse Cardiac 
Events: Sumatriptan should not be given to patients with documented ischemic or vasospastic CAD 
(see CONTRAINDICATIONS). It is strongly recommended that sumatriptan not be given to 
patients in whom unrecognized coronary artery disease (CAD) is predicted by the presence of risk 
factors (e.g., hypertension, hypercholesterolemia, smoker, obesity, diabetes, strong family history of 
CAD, female with surgical or physiological menopause, or male over 40 years of age) unless a 
cardiovascular evaluation provides satisfactory clinical evidence that the patient is reasonably free 
of coronary artery and ischemic myocardial disease or other significant underlying cardiovascular 
disease. The sensitivity of cardiac diagnostic procedures to detect cardiovascular disease or 
predisposition to coronary artery vasospasm is modest, at best. If, during the cardiovascular 
evaluation, the patient's medical history or electrocardiographic investigations reveal findings 
indicative of or consistent with coronary artery vasospasm or myocardial ischemia, sumatriptan 
should not be administered (see CONTRAINDICATIONS). 
  
For patients with risk factors predictive of CAD who are determined to have a satisfactory 
cardiovascular evaluation, it is strongly recommended that administration of the first dose of 
sumatriptan injection take place in the setting of a physician's office or similar medically staffed and 
equipped facility. Because cardiac ischemia can occur in the absence of clinical symptoms, 
consideration should be given to obtaining on the first occasion of use an electrocardiogram (ECG) 
during the interval immediately following sumatriptan succinate injection, in these patients with risk 
factors. 
  
It is recommended that patients who are intermittent long-term users of sumatriptan and who have 
or acquire risk factors predictive of CAD, as described above, undergo periodic interval 
cardiovascular evaluation as they continue to use sumatriptan. In considering this recommendation 
for periodic cardiovascular evaluation, it is noted that patients with cluster headache are 
predominantly male and over 40 years of age, which are risk factors for CAD. 
  
The systematic approach described above is intended to reduce the likelihood that patients with 
unrecognized cardiovascular disease will be inadvertently exposed to sumatriptan. 
  
Drug-Associated Cardiac Events and Fatalities: See WARNINGS, Drug-Associated Cardiac 
Events and Fatalities in the oral product information. 
  
Premarketing Experience with Sumatriptan: See WARNINGS, Premarketing Experience with 
Sumatriptan in the oral product information. 
  
Postmarketing Experience: See WARNINGS, Postmarketing Experience in the oral product 
information. 
  
Drug-Associated Cerebrovascular Events and Fatalities: See WARNINGS, Drug-Associated 
Cerebrovascular Events and Fatalities in the oral product information. 
  
Other Vasospasm-Related Events: See WARNINGS, Other Vasospasm-Related Events in the 
oral product information. 
  
Increase in Blood Pressure: See WARNINGS, Increase in Blood Pressure in the oral product 
information. 
  
Concomitant Drug Use: In patients taking MAO-A inhibitors, sumatriptan plasma levels attained 
after treatment with recommended doses are nearly double those obtained under other conditions. 
Accordingly, the coadministration of sumatriptan and an MAO-A inhibitor is not generally 
recommended. If such therapy is clinically warranted, however, suitable dose adjustment and 
appropriate observation of the patient is advised (see CLINICAL PHARMACOLOGY). 
  
Use in Women of Childbearing Potential: See PRECAUTIONS. 
  
Hypersensitivity: See WARNINGS, Hypersensitivity in the oral product information. 
  
PRECAUTIONS 
  
General 
  
Chest, jaw, or neck tightness is relatively common after administration of sumatriptan succinate 
injection. Chest discomfort and jaw or neck tightness has been reported following use of 
sumatriptan succinate tablets and has also been reported infrequently following the administration of 
sumatriptan nasal spray. Only rarely have these symptoms been associated with ischemic ECG 
changes. However, because sumatriptan may cause coronary artery vasospasm, patients who 
experience signs or symptoms suggestive of angina following sumatriptan should be evaluated for 
the presence of CAD or a predisposition to Prinzmetal variant angina before receiving additional 
doses of sumatriptan and should be monitored electrocardiographically if dosing is resumed and 
similar symptoms recur. Similarly, patients who experience other symptoms or signs suggestive of 
decreased arterial flow, such as ischemic bowel syndrome or Raynaud syndrome, following 
sumatriptan should be evaluated for atherosclerosis or predisposition to vasospasm (see 
WARNINGS). 
  
Sumatriptan succinate injection should also be administered with caution to patients with diseases 
that may alter the absorption, metabolism, or excretion of drugs, such as impaired hepatic or renal 
function. 
  
There have been rare reports of seizure following administration of sumatriptan. Sumatriptan should 
be used with caution in patients with a history of epilepsy or structural brain lesions that lower their 
seizure threshold. 
  
Care should be taken to exclude other potentially serious neurologic conditions before treating 
headache in patients not previously diagnosed with migraine or cluster headache or who experience 
a headache that is atypical for them. There have been rare reports where patients received 
sumatriptan for severe headaches that were subsequently shown to have been secondary to an 
evolving neurologic lesion (see WARNINGS). For a given attack, if a patient does not respond to 
the first dose of sumatriptan, the diagnosis of migraine or cluster headache should be reconsidered 
before administration of a second dose. 
  
Binding to Melanin-Containing Tissues 
  
Because sumatriptan binds to melanin, it could accumulate in melanin-rich tissues (such as the eye) 
over time. This raises the possibility that sumatriptan could cause toxicity in these tissues after 
extended use. However, no effects on the retina related to treatment with sumatriptan were noted 
in any of the toxicity studies. Although no systematic monitoring of ophthalmologic function was 
undertaken in clinical trials, and no specific recommendations for ophthalmologic function was 
undertaken in clinical trials, and no specific recommendations for ophthalmologic monitoring are 
offered, prescribers should be aware of the possibility of long-term ophthalmologic effects (see 
CLINICAL PHARMACOLOGY). 
  
Corneal Opacities 
  
Sumatriptan causes corneal opacities and defects in the corneal epithelium in dogs; this raises the 
possibility that these changes may occur in humans. While patients were not systematically 
evaluated for these changes in clinical trials, and no specific recommendations for monitoring are 
being offered, prescribers should be aware of the possibility of these changes (see CLINICAL 
PHARMACOLOGY). 
  
Patients who are advised to self-administer sumatriptan succinate injection in medically 
unsupervised situations should receive instruction on the proper use of the product from 
the physician or other suitably qualified health care professional prior to doing so for the 
first time. 
  
Information for the Patient 
  
With the autoinjector, the needle penetrates approximately ¼ of an inch (5 to 6 mm). Since the 
injection is intended to be given subcutaneously, intramuscular or intravascular delivery should be 
avoided. Patients should be directed to use injection sites with an adequate skin and subcutaneous 
thickness to accommodate the length of the needle. See PATIENT PACKAGE INSERT at the 
end of the Intranasal product information for additional information for patients. 
  
Laboratory Tests 
  
No specific laboratory tests are recommended for monitoring patients prior to and/or after treatment 
with sumatriptan. 
  
Drug/Laboratory Test Interactions 
  
Sumatriptan succinate is not known to interfere with commonly employed clinical laboratory tests. 
  
Carcinogenesis, Mutagenesis, and Impairment of Fertility 
  
In carcinogenicity studies, rats and mice were given sumatriptan by oral gavage (rats: 104 weeks), 
or drinking water (mice: 78 weeks). Average exposures achieved in mice receiving the highest dose 
were approximately 110 times the exposure attained in humans after the maximum recommended 
single dose of 6 mg. The highest dose to rats was approximately 260 times the maximum single 
dose of 6 mg on a mg/m2 basis. There was no evidence of an increase in tumors in either species 
related to sumatriptan administration. 
  
Sumatriptan was not mutagenic in the presence or absence of metabolic activation when tested in 
two gene mutation assays (the Ames test and the in vitro mammalian Chinese hamster 
V79/HGPRT assay). In two cytogenetics assays (the in vitro human lymphocyte assay and the in 
vivo rat micronucleus assay) sumatriptan was not associated with clastogenic activity. 
  
A fertility study (Segment I) by the subcutaneous route, during which male and female rats were 
dosed daily with sumatriptan prior to and throughout the mating period, has shown no evidence of 
impaired fertility at doses equivalent to approximately 100 times the maximum recommended single 
human dose of 6 mg on a mg/m2 basis. However, following oral administration, a treatment-related 
decrease in fertility, secondary to a decrease in mating, was seen for rats treated with 50 and 500 
mg/kg per day. The no-effect dose for this finding was approximately eight times the maximum 
recommended single human dose of 6 mg on a mg/m2 basis. It is not clear whether the problem is 
associated with the treatment of males or females or both. 
  
Pregnancy Category C 
  
Sumatriptan has been shown to be embryolethal in rabbits when given daily at a dose approximately 
equivalent to the maximum recommended single human subcutaneous dose of 6 mg on a mg/m2 
basis. There is no evidence that establishes that sumatriptan is a human teratogen; however, there 
are no adequate and well-controlled studies in pregnant women. Sumatriptan succinate injection 
should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. 
  
In assessing this information, the following additional findings should be considered. 
  
Embryolethality: When given intravenously to pregnant rabbits daily throughout the period of 
organogenesis, sumatriptan caused embryolethality at doses at or close to those producing maternal 
toxicity. The mechanism of the embryolethality is not known. These doses were approximately 
equivalent to the maximum single human dose of 6 mg on a mg/m2 basis. 
  
The intravenous administration of sumatriptan to pregnant rats throughout organogenesis at doses 
that are approximately 20 times a human dose of 6 mg on a mg/m2 basis, did not cause 
embryolethality. Additionally, in a study of pregnant rats given subcutaneous sumatriptan daily prior 
to and throughout pregnancy, there was no evidence of increase embryo/fetal lethality. 
  
Teratogenicity: Term fetuses from Dutch Stride rabbits treated during organogenesis with oral 
sumatriptan exhibited an increased incidence of cervicothoracic vascular and skeletal abnormalities. 
The functional significance of these abnormalities is not known. The highest no-effect dose for 
these effects was 15 mg/kg per day, approximately 50 times the maximum single dose of 6 mg on a 
mg/m2 basis. 
  
In a study in rats dosed daily with subcutaneous sumatriptan prior to and throughout pregnancy, 
there was no evidence of teratogenicity. 
  
To monitor fetal outcomes of pregnant women exposed to sumatriptan succinate, Glaxo Wellcome 
Inc. maintains a Sumatriptan Pregnancy Registry. Physicians are encouraged to register patients by 
calling (800) 336–2176. 
  
Nursing Mothers 
  
Sumatriptan is excreted in human breast milk. Therefore, caution should be exercised when 
considering the administration of any form of sumatriptan succinate to a nursing woman. 
  
Pediatric Use 
  
See PRECAUTIONS, Pediatric Use in the oral product information. 
  
Geriatric Use 
  
The use of sumatriptan in elderly patients is not recommended because elderly patients are more 
likely to have decreased hepatic function, they are at higher risk for CAD, and blood pressure 
increases may be more pronounced in the elderly (see WARNINGS).