WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
Tolerance
Excessive use may lead to the development of tolerance.
Only the smallest number of doses required for effective relief of the acute
angina attack should be used [see DOSAGE AND ADMINISTRATION].
Hypotension
Severe hypotension, particularly with upright posture,
may occur even with small doses of nitroglycerin particularly in patients with
constrictive pericarditis, aortic or mitral stenosis, patients who may be
volume-depleted, or are already hypotensive. Hypotension induced by
nitroglycerin may be accompanied by paradoxical bradycardia and increased
angina pectoris. Symptoms of severe hypotension (nausea, vomiting, weakness,
pallor, perspiration and collapse/syncope) may occur even with therapeutic
doses.
Hypertrophic Obstructive Cardiomyopathy
Nitrate therapy may aggravate the angina caused by
hypertrophic obstructive cardiomyopathy.
Headache
Nitroglycerin produces dose-related headaches, especially
at the start of nitroglycerin therapy, which may be severe and persistent but
usually subside with continued use.
Patient Counseling Information
Advise the patient to read the FDA-approved patient
labeling (Instructions for Use)
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Animal carcinogenesis studies with sublingual
nitroglycerin have not been performed.
Rats receiving up to 434 mg/kg/day of dietary
nitroglycerin for 2 years developed dose-related fibrotic and neoplastic
changes in liver, including carcinomas, and interstitial cell tumors in testes.
At high dose, the incidences of hepatocellular carcinomas in both sexes were 52
% vs. 0 % in controls, and incidences of testicular tumors were 52 % vs. 8 % in
controls. Lifetime dietary administration of up to 1058 mg/kg/day of
nitroglycerin was not tumorigenic in mice.
Nitroglycerin was weakly mutagenic in Ames tests
performed in two different laboratories. There was no evidence of mutagenicity
in an in vivo dominant lethal assay with male rats treated with doses up to
about 363 mg/kg/day, p.o., or in in vitro cytogenic tests in rat and dog
tissues and for chromosomal aberration in Chinese hamster ovary cells.
In a three-generation reproduction study, rats received
dietary nitroglycerin at doses up to about 434 mg/kg/day for six months prior
to mating of the F0 generation with treatment continuing through successive F1 and
F2 generations. The high dose was associated with decreased feed intake and
body weight gain in both sexes at all matings. No specific effect on the
fertility of the F0 generation was seen. Infertility noted in subsequent
generations, however, was attributed to increased interstitial cell tissue and
aspermatogenesis in the high-dose males. In this three-generation study there
was no clear evidence of teratogenicity.
Use In Specific Populations
Pregnancy
Risk summary
Limited published data on the use of nitroglycerin are
insufficient to determine a drug associated risk of major birth defects or
miscarriage. In animal reproduction studies, there were no adverse
developmental effects when nitroglycerin was administered intravenously to
rabbits or intraperitoneally to rats during organogenesis at doses greater than
64-times the human dose [see Data].
The estimated background risk of major birth defects and
miscarriage for the indicated population is unknown. In the U.S. general
population, the estimated background risk of major birth defects and
miscarriage in clinically recognized pregnancies is 2 – 4% and 15 – 20%,
respectively.
Data
Animal Data
No embryotoxic or postnatal development effects were
observed with transdermal application in pregnant rabbits and rats at doses up
to 240 mg/kg/day for 13 days, at intraperitoneal doses in pregnant rats up to
20 mg/kg/day for 11 days, and at intravenous doses in pregnant rabbits up to 4
mg/kg/day for 13 days.
Lactation
Risk summary
Sublingual nitroglycerin has not been studied in
lactating women. It is not known if nitroglycerin is present in human milk or
if nitroglycerin has effects on milk production. The developmental and health
benefits of breastfeeding should be considered along with the mother's clinical
need for nitroglycerin and any potential adverse effects on the breastfed child
from nitroglycerin or from the underlying maternal condition.
Pediatric Use
Safety and effectiveness of nitroglycerin in pediatric
patients have not been established.
Geriatric Use
Clinical studies did not include sufficient numbers of
subjects aged 65 and over to determine whether they respond differently from
younger subjects. Other reported clinical experience has not identified
differences in responses between elderly (greater than or equal to 65 years)
and younger (less than 65 years) patients. In general, dose selection for an
elderly patient should start at the low end of the dosing range, reflecting the
greater frequency of decreased hepatic, renal, or cardiac function, and of
concomitant disease or other drug therapy.