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Isradipine Pregnancy and Breastfeeding Warnings

Medically reviewed by Last updated on Mar 6, 2023.

Isradipine is also known as: DynaCirc CR, Dynacirc

Isradipine Pregnancy Warnings

Isradipine has been assigned to pregnancy category C by the FDA. Animal studies have failed to reveal evidence of embryotoxicity at doses which were safe to the mother. There is no evidence of teratogenicity at any dose tested. Animal studies have revealed decreased maternal weight gain at doses up to 150 times the maximum recommended human dose (on a per kg basis), but there were no lasting effects on either the mother or offspring. A controlled study from human pregnancy is available that demonstrates isradipine may be used safely and efficaciously to treat pregnancy-induced hypertension without significantly affecting uterine blood flow. Isradipine should be given during pregnancy only when benefit outweighs risk.

Isradipine crosses the placental barrier, with a fetal to maternal plasma concentration ratio varying between 0.25 and 0.85. There are no known negative effects on neonatal outcome after isradipine 5 mg twice a day.

At least 4 studies (2 using 0.3 mg IV, 1 using 5 mg PO BID, and on using 2.5 mg PO BID) have shown that isradipine can effectively and safely lower blood pressure without altering umbilical and uterine artery blood flow. Doses up to 1.5 mg IV to normotensive women has resulted in a 10% reduction in uterine contractility, significant hypotension in at least one case, and a mean increase in maternal heart rate by 20% to 30%. The various features of the fetal heart rate pattern, as evaluated in a controlled trial by computerized cardiotocography in human pregnancy, were not influenced by isradipine SR 5 mg twice a day in 23 women with preeclampsia.

Because limited data have failed to show that the use of isradipine can effectively lower blood pressure in pregnant patients with hypertension and proteinuria, some experts believe that isradipine is not effective for the treatment of preeclampsia.

See references

Isradipine Breastfeeding Warnings

There are no data on the excretion of isradipine into human milk. The manufacturer recommends that due to the potential for serious adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

See references

References for pregnancy information

  1. Wide-Swensson D, Ingemarsson I, Arulkumaran S, Andersson KE "Effects of isradipine, a new calcium antagonist, on maternal cardiovascular system and uterine activity in labour." Br J Obstet Gynaecol 97 (1990): 945-9
  2. Feiks A, Grunberger W, Meisner W "Influence of isradipine on the maternal and fetal cardiovascular system in hypertensive disorders in pregnancy." Am J Hypertens 4 (1991): s200-2
  3. Lunell NO, Bondesson U, Grunewald C, Ingemarsson I, Nisell H, Wide-Swensson D "Transplacental passage of isradipine in the treatment of pregnancy-induced hypertension." Am J Hypertens 6 (1993): s110-1
  4. Ingemarsson I, Wide-Swensson D, Andersson KE, Arulkumaran S "Maternal and fetal cardiovascular changes after intravenous injections of isradipine to pregnant women." Drugs 40 (1990): 58-9
  5. Lunell NO, Garoff L, Grunewald C, Nisell H, Nylund L, Sarby B, Thornstrom S "Isradipine, a new calcium antagonist: effects on maternal and fetal hemodynamics." J Cardiovasc Pharmacol 18 (1991): S37-40
  6. "Product Information. Dynacirc (isradipine)." Sandoz Pharmaceuticals Corporation
  7. Wideswensson D, Montan S, Arulkumaran S, Ingemarsson I, Ratnam SS "Effect of methyldopa and isradipine on fetal heart rate pattern assessed by computerized cardiotocography in human pregnancy." Am J Obstet Gynecol 169 (1993): 1581-5
  8. Kublickiene KR, Wolff K, Kublickas M, Lindblom B, Lunell NO, Nisell H "Effects of isradipine on endothelin-induced constriction of myometrial arteries in normotensive pregnant women." Am J Hypertens 7 Suppl 7 (1994): s50-5
  9. Maharaj B, Khedun SM, Moodley J, Madhanpall N, Vanderbyl K "Intravenous isradipine in the management of severe hypertension in pregnant and nonpregnant patients - a pilot study." Am J Hypertens 7 Suppl 7 (1994): s61-3
  10. Brogden RN, Sorkin EM "Isradipine: an update of its pharmacodynamic and pharmacokinetic properties and therapeutic efficacy in the treatment of mild to moderate hypertension." Drugs 49 (1995): 618-49
  11. Wideswensson DH, Ingemarsson I, Lunell NO, Forman A, Skajaa K, Lindberg B, Lindeberg S, Marsal K, Andersson KE "Calcium channel blockade (isradipine) in treatment of hypertension in pregnancy: a randomized placebo-controlled study." Am J Obstet Gynecol 173 (1995): 872-8
  12. Kublickas M, Lunell NO, Grunewald C, Nisell H "Effect of isradipine on maternal renal artery pulsatility index in hypertensive pregnancy." Hypertens Pregnancy 14 (1995): 277-85
  13. Montan S, Anandakumar C, Arulkumaran S, Ingemarsson I, Ratnam SS "Randomised controlled trial of methyldopa and isradipine in preeclampsia - effects on uteroplacental and fetal hemodynamics." J Perinat Med 24 (1996): 177-84

References for breastfeeding information

  1. "Product Information. Dynacirc (isradipine)." Sandoz Pharmaceuticals Corporation

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.