r inhibitors, such as atomoxetine ergot alkaloids, such as methylergonovine maleate 7.2 interactions that antagonize the pressor effect the increasing blood pressure effect of phenylephrine hydrochloride injection is decreased in patients receiving: α-adrenergic antagonists phosphodiesterase type 5 inhibitors mixed α- and β-receptor antagonists calcium channel blockers, such as nifedipine benzodiazepines ace inhibitors centrally acting sympatholytic agents, such as reserpine, guanfacine

rlying heart failure, and increase pulmonary arterial pressure. 5.2 peripheral and visceral ischemia phenylephrine hydrochloride injection can cause excessive peripheral and visceral vasoconstriction and ischemia to vital organs, particularly in patients with extensive peripheral vascular disease. 5.3 skin and subcutaneous necrosis extravasation of phenylephrine hydrochloride injection can cause necrosis or sloughing of tissue. the infusion site should be checked for free flow. care should be taken to avoid extravasation of phenylephrine hydrochloride injection. 5.4 bradycardia phenylephrine hydrochloride injection can cause severe bradycardia and decreased cardiac output. 5.5 allergic reactions phenylephrine hydrochloride injection contains sodium metabisulfite, a sulfite that may cause allergic-type reactions, including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. the overall prevalence of sulfite sensitivity in the general population is unknown and probably low. sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people. 5.6 renal toxicity phenylephrine hydrochloride injection can increase the need for renal replacement therapy in patients with septic shock. monitor renal function. 5.7 risk of augmented pressor affect in patients with autonomic dysfunction the increasing blood pressure response to adrenergic drugs, including phenylephrine hydrochloride injection, can be increased in patients with autonomic dysfunction, as may occur with spinal cord injuries. 5.8 pressor effect with concomitant oxytocic drugs oxytocic drugs potentiate the increasing blood pressure effect of sympathomimetic pressor amines including phenylephrine hydrochloride injection [see drug interactions ( 7.1 )] , with the potential for hemorrhagic stroke.

to administration. do not use if the solution is colored or cloudy, or if it contains particulate matter. the diluted solution should not be held for more than 4 hours at room temperature or for more than 24 hours under refrigerated conditions. discard any unused portion. during phenylephrine hydrochloride injection administration: correct intravascular volume depletion. correct acidosis. acidosis may reduce the effectiveness of phenylephrine. 2.2 dosing for treatment of hypotension during anesthesia the following are the recommended dosages for the treatment of hypotension during anesthesia. the recommended initial dose is 40 to 100 mcg administered by intravenous bolus. additional boluses may be administered every 1 to 2 minutes as needed; not to exceed a total dosage of 200 mcg. if blood pressure is below the target goal, start a continuous intravenous infusion with an infusion rate of 10 to 35 mcg/minute; not to exceed 200 mcg/minute. adjust dosage according to the blood pressure goal. 2.3 prepare a 100 mcg/ml solution for bolus intravenous administration for bolus intravenous administration, prepare a solution containing a final concentration of 100 mcg/ml of phenylephrine hydrochloride injection: withdraw 10 mg (1 ml of 10 mg/ml) of phenylephrine hydrochloride injection and dilute with 99 ml of 5% dextrose injection or 0.9% sodium chloride injection. withdraw an appropriate dose from the 100 mcg/ml solution prior to bolus intravenous administration. 2.4 prepare a solution for continuous intravenous administration for continuous intravenous infusion, prepare a solution containing a final concentration of 20 mcg/ml of phenylephrine hydrochloride injection in 5% dextrose injection or 0.9% sodium chloride injection: withdraw 10 mg (1 ml of 10 mg/ml) of phenylephrine hydrochloride injection and dilute with 500 ml of 5% dextrose injection or 0.9% sodium chloride injection. 2.5 directions for dispensing from pharmacy bulk vial the pharmacy bulk vial is intended for dispensing of single doses to multiple patients in a pharmacy admixture program and is restricted to the preparation of admixtures for infusion. each closure shall be penetrated only one time with a suitable sterile transfer device or dispensing set that allows measured dispensing of the contents. the pharmacy bulk vial is to be used only in a suitable work area such as a laminar flow hood (or an equivalent clean air compounding area). dispensing from a pharmacy bulk vial should be completed within 4 hours after the vial is penetrated.

uspected adverse reactions, contact par pharmaceutical at 1-800-828-9393 or fda at 1-800-fda-1088 or www.fda.gov/medwatch.

r inhibitors, such as atomoxetine ergot alkaloids, such as methylergonovine maleate 7.2 interactions that antagonize the pressor effect the increasing blood pressure effect of phenylephrine hydrochloride injection is decreased in patients receiving: α-adrenergic antagonists phosphodiesterase type 5 inhibitors mixed α- and β-receptor antagonists calcium channel blockers, such as nifedipine benzodiazepines ace inhibitors centrally acting sympatholytic agents, such as reserpine, guanfacine

fect, 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. clinical considerations disease-associated maternal and/or embryofetal risk untreated hypotension associated with spinal anesthesia for cesarean section is associated with an increase in maternal nausea and vomiting. a sustained decrease in uterine blood flow due to maternal hypotension may result in fetal bradycardia and acidosis. data human data published randomized controlled trials over several decades, which compared the use of phenylephrine injection to other similar agents in pregnant women during cesarean section, have not identified adverse maternal or infant outcomes. at recommended doses, phenylephrine does not appear to affect fetal heart rate or fetal heart rate variability to a significant degree. there are no studies on the safety of phenylephrine injection exposure during the period of organogenesis, and therefore, it is not possible to draw any conclusions on the risk of birth defects following exposure to phenylephrine injection during pregnancy. in addition, there are no data on the risk of miscarriage following fetal exposure to phenylephrine injection. animal data no clear malformations or fetal toxicity were reported when normotensive pregnant rabbits were treated with phenylephrine via continuous intravenous infusion over 1 hour (0.5 mg/kg/day; approximately equivalent to a hdd based on body surface area) from gestation day 7 to 19. at this dose, which demonstrated no maternal toxicity, there was evidence of developmental delay (altered ossification of sternebra). in a non-glp dose range-finding study in normotensive pregnant rabbits, fetal lethality and cranial, paw, and limb malformations were noted following treatment with 1.2 mg/kg/day of phenylephrine via continuous intravenous infusion over 1 hour (2.3-times the hdd). this dose was clearly maternally toxic (increased mortality and significant body weight loss). an increase in the incidence of limb malformation (hyperextension of the forepaw) coincident with high fetal mortality was noted in a single litter at 0.6 mg/kg/day (1.2-times the hdd) in the absence of maternal toxicity. no malformations or embryo-fetal toxicity were reported when normotensive pregnant rats were treated with up to 3 mg/kg/day phenylephrine via continuous intravenous infusion over 1 hour (2.9-times the hdd) from gestation day 6 to 17. this dose was associated with some maternal toxicity (decreased food consumption and body weights). decreased pup weights were reported in a pre-and postnatal development toxicity study in which normotensive pregnant rats were administered phenylephrine via continuous intravenous infusion over 1 hour (0.3, 1.0, or 3.0 mg/kg/day; 0.29, 1, or 2.9 times the hdd) from gestation day 6 through lactation day 21). no adverse effects on growth and development (learning and memory, sexual development, and fertility) were noted in the offspring of pregnant rats at any dose tested. maternal toxicities (mortality late in gestation and during lactation period, decreased food consumption and body weight) occurred at 1 and 3 mg/kg/day of phenylephrine (equivalent to and 2.9 times the hdd, respectively). 8.2 lactation risk summary there are no data on the presence of phenylephrine hydrochloride injection or its metabolite in human or animal milk, the effects on the breastfed infant, or the effects on milk production. the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for phenylephrine hydrochloride injection and any potential adverse effects on the breastfed infant from phenylephrine hydrochloride injection or from the underlying maternal condition. 8.4 pediatric use safety and effectiveness in pediatric patients have not been established. 8.5 geriatric use clinical studies of phenylephrine 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 the elderly and younger patients. in general, dose selection for an elderly patient should be cautious, usually starting 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. 8.6 hepatic impairment in patients with liver cirrhosis [child pugh class b and class c], dose-response data indicate decreased responsiveness to phenylephrine. start dosing in the recommended dose range, but more phenylephrine may be needed in this population. 8.7 renal impairment in patients with end stage renal disease (esrd), dose-response data indicate increased responsiveness to phenylephrine. consider starting at the lower end of the recommended dose range, and adjusting dose based on the target blood pressure goal.

utcomes. 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. clinical considerations disease-associated maternal and/or embryofetal risk untreated hypotension associated with spinal anesthesia for cesarean section is associated with an increase in maternal nausea and vomiting. a sustained decrease in uterine blood flow due to maternal hypotension may result in fetal bradycardia and acidosis. data human data published randomized controlled trials over several decades, which compared the use of phenylephrine injection to other similar agents in pregnant women during cesarean section, have not identified adverse maternal or infant outcomes. at recommended doses, phenylephrine does not appear to affect fetal heart rate or fetal heart rate variability to a significant degree. there are no studies on the safety of phenylephrine injection exposure during the period of organogenesis, and therefore, it is not possible to draw any conclusions on the risk of birth defects following exposure to phenylephrine injection during pregnancy. in addition, there are no data on the risk of miscarriage following fetal exposure to phenylephrine injection. animal data no clear malformations or fetal toxicity were reported when normotensive pregnant rabbits were treated with phenylephrine via continuous intravenous infusion over 1 hour (0.5 mg/kg/day; approximately equivalent to a hdd based on body surface area) from gestation day 7 to 19. at this dose, which demonstrated no maternal toxicity, there was evidence of developmental delay (altered ossification of sternebra). in a non-glp dose range-finding study in normotensive pregnant rabbits, fetal lethality and cranial, paw, and limb malformations were noted following treatment with 1.2 mg/kg/day of phenylephrine via continuous intravenous infusion over 1 hour (2.3-times the hdd). this dose was clearly maternally toxic (increased mortality and significant body weight loss). an increase in the incidence of limb malformation (hyperextension of the forepaw) coincident with high fetal mortality was noted in a single litter at 0.6 mg/kg/day (1.2-times the hdd) in the absence of maternal toxicity. no malformations or embryo-fetal toxicity were reported when normotensive pregnant rats were treated with up to 3 mg/kg/day phenylephrine via continuous intravenous infusion over 1 hour (2.9-times the hdd) from gestation day 6 to 17. this dose was associated with some maternal toxicity (decreased food consumption and body weights). decreased pup weights were reported in a pre-and postnatal development toxicity study in which normotensive pregnant rats were administered phenylephrine via continuous intravenous infusion over 1 hour (0.3, 1.0, or 3.0 mg/kg/day; 0.29, 1, or 2.9 times the hdd) from gestation day 6 through lactation day 21). no adverse effects on growth and development (learning and memory, sexual development, and fertility) were noted in the offspring of pregnant rats at any dose tested. maternal toxicities (mortality late in gestation and during lactation period, decreased food consumption and body weight) occurred at 1 and 3 mg/kg/day of phenylephrine (equivalent to and 2.9 times the hdd, respectively).

life was approximately 5 minutes. the steady-state volume of distribution of approximately 340 l suggests a high distribution into organs and peripheral tissues. the average total serum clearance is approximately 2100 ml/min. the observed phenylephrine plasma terminal elimination half-life was 2.5 hours. phenylephrine is metabolized primarily by monoamine oxidase and sulfotransferase. after intravenous administration of radiolabeled phenylephrine, approximately 80% of the total dose was eliminated within first 12 h; and approximately 86% of the total dose was recovered in the urine within 48 h. the excreted unchanged parent drug was 16% of the total dose in the urine at 48 h post intravenous administration. there are two major metabolites, with approximately 57 and 8% of the total dose excreted as m -hydroxymandelic acid and sulfate conjugates, respectively. the metabolites are considered not pharmacologically active.

es are considered not pharmacologically active.

oma assay. impairment of fertility phenylephrine did not impair mating, fertility, or reproductive outcome in normotensive male rats treated with 3 mg/kg/day phenylephrine via continuous intravenous infusion over 1 hour (2.9 times the hdd) for 28 days prior to mating and for a minimum of 63 days prior to sacrifice and female rats treated with the same dosing regimen for 14 days prior to mating and through gestation day 6. this dose was associated with increased mortality in both male and female rats and decreased body weight gain in treated males. there were decreased caudal sperm density and increased abnormal sperm reported in males treated with 3 mg/kg/day phenylephrine (2.9 times the hdd).

ertility phenylephrine did not impair mating, fertility, or reproductive outcome in normotensive male rats treated with 3 mg/kg/day phenylephrine via continuous intravenous infusion over 1 hour (2.9 times the hdd) for 28 days prior to mating and for a minimum of 63 days prior to sacrifice and female rats treated with the same dosing regimen for 14 days prior to mating and through gestation day 6. this dose was associated with increased mortality in both male and female rats and decreased body weight gain in treated males. there were decreased caudal sperm density and increased abnormal sperm reported in males treated with 3 mg/kg/day phenylephrine (2.9 times the hdd).