Warnings for Zovirax Cream
Included as part of the PRECAUTIONS section.
Precautions for Zovirax Cream
Cardiovascular Reactions
Severe or life-threatening cardiovascular reactions including cardiac arrest, arrhythmia, asystole, second degree atrioventricular block, hypotension, elevation in blood pressure, bradycardia, and tachycardia have been reported generally within 60 minutes following administration of indigotindisulfonate sodium injection products and required urgent intervention [see ADVERSE REACTIONS].
Indigotindisulfonate may cause vasoconstriction by interference with vasodilation mediated by nitric oxide dependent mechanisms and by direct vasoconstriction. Indigotindisulfonate may also cause hypotension. Patients with hypertension, heart rate and conduction disorders, or medications causing bradycardia may be at increased risk for elevated blood pressure, hypotension, and bradycardia.
Closely monitor blood pressure and cardiac rhythm during and following the injection of BLUDIGO. Interrupt administration if reactions are observed.
Hypersensitivity Reactions
Serious anaphylactic reactions with hypotension, dyspnea, bronchospasm, urticaria, or erythema have been reported with the use of indigotindisulfonate sodium injection products [see ADVERSE REACTIONS]. BLUDIGO is contraindicated in patients with known hypersensitivity to indigotindisulfonate [see CONTRAINDICATIONS]. Monitor patients for anaphylactic reactions and have emergency equipment and trained personnel readily available.
Interference With Oximetry Measurements
Indigotindisulfonate has been reported to interfere with light absorption and transiently interfere with pulse oximetric methods. Anesthesiologists should be aware of the potential for artifactual reduction in SpO2 when anesthetized patients are administered BLUDIGO.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Carcinogenicity
Carcinogenicity studies in animals have not been conducted with indigotindisulfonate sodium using the intravenous route of administration.
Long-term studies in mice with oral and subcutaneous administration of indigotindisulfonate sodium revealed no carcinogenic effects.
Mutagenesis
Although indigotindisulfonate sodium has been evaluated in a number of Ames assay studies, an Ames assay study that follows all currently recommended guidelines has not been performed. Indigotindisulfonate was not genotoxic in all those Ames assays. The mutagenicity of indigotindisulfonate was inconclusive in the in vitro mouse L5187Y Lymphoma TK +/-assay. Orally administered indigotindisulfonate was not mutagenic in the in vivo mouse micronucleus test. An in vivo micronucleus test with indigotindisulfonate sodium using the intravenous route of administration has not been conducted.
Fertility
Fertility studies with indigotindisulfonate sodium using the intravenous route of administration have not been conducted.
Use In Specific Populations
Pregnancy
Risk Summary
Available data from case reports, case series, observational studies and clinical experience with indigotindisulfonate sodium injection use in pregnant women over several decades have not identified a drug associated risk of adverse maternal and fetal adverse effects. Indigotindisulfonate sodium injection use during the first trimester of pregnancy is rare; thus, the data are insufficient to evaluate for a drug associated risk of major birth defects and miscarriage. The majority of the published data were from intra-amniotic injections. Animal reproduction studies using the intravenous route of administration have not been conducted. Oral administration of indigotindisulfonate sodium to pregnant rats and rabbits produced no evidence of fetal harm. However, oral availability is low (3%) so that the risk of intravenous administration of indigotindisulfonate sodium during pregnancy cannot be evaluated from the data available.
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defects, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.
Lactation
Risk Summary
It is not known if indigotindisulfonate is present in animal or human milk. The transfer of indigotindisulfonate into breastmilk is likely to be low and adverse effects on the breastfed infant are not expected [see CLINICAL PHARMACOLOGY]. There are no data on the effect of indigotindisulfonate on the breastfed infant or milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for BLUDIGO and any potential adverse effects on the breastfed infant from BLUDIGO or from the underlying maternal condition.
Pediatric Use
The safety and effectiveness of BLUDIGO have not been established in pediatric patients.
Geriatric Use
Of the total number of subjects in the clinical study of BLUDIGO, 23 (20%) were 65 to 74 years of age, and 12 (10%) were 75 and older. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out.
Renal Impairment
Indigotindisulfonate is known to be excreted by the kidney through tubular secretion. No dedicated pharmacokinetic study using BLUDIGO in patients with varying degree of renal impairment has been conducted. Based on subgroup analyses in the randomized clinical trial, dose adjustment is not needed in patients with mild to moderate renal impairment (estimated glomerular filtration rate (eGFR) 30 to 89 mL/min derived from the Modification of Diet in Renal Disease formula).
BLUDIGO has not been studied in patients with eGFR < 30 mL/min and is not recommended for use in these patients.