Iranian Journal of Neurology 2017. 16(3):125-129.

The comparison of anti-seizure and tocolytic effects of phenytoin and magnesium sulphate in the treatment of eclampsia and preeclampsia: A randomised clinical trial
Maryam Khooshideh, Majid Ghaffarpour, Sama Bitarafan


Background: To date, magnesium sulphate (MgSO4) is the treatment of choice for prevention of seizure in eclampsia and preeclampsia. However, there are some limitations in the administration of MgSO4 due to its tocolytic effects. The aim of this study was to compare the anticonvulsant and tocolytic effects of MgSO4 and another drug, phenytoin, in patients with eclampsia and preeclampsia.

Methods: This clinical trial was conducted on pregnant women hospitalised with eclampsia or preeclampsia, during 2014–2016. The subjects were randomly assigned to two treatment groups using blocking method based on disease (eclampsia or mild and severe preeclampsia). One group received MgSO4 (group M) and another group received phenytoin (group P) as treatment. Each group consisted of 110 and 65 women with mild and severe preeclampsia, respectively (subgroup A), and 25 women with eclampsia (subgroup B). Duration of labor, the number of cesarean sections, convulsions and Apgar scores of infants were compared between the two groups and were considered as treatment outcomes.

Results: Convulsion rate was significantly lower with MgSO4 than phenytoin (P = 0.001). No seizure occurred in patients with mild preeclampsia in group P. Duration of stage one of labor (P < 0.001) and the number of cesarean sections (P = 0.040) were significantly higher in group M. However, one-minute Apgar scores for newborns were higher in women treated with MgSO4 compared to that of phenytoin
(P = 0.001). Five-minute Apgar was not significantly different.

Conclusion: Although MgSO4 is more effective than phenytoin for prevention of convulsion in eclampsia and severe preeclampsia, phenytoin may be considered for treatment of special conditions such as mild preeclampsia. Due to the tocolytic effects of MgSO4 on increasing the duration of labor, the increased risk of cesarean section and the potential for toxicity, physicians should critically consider the best drug according to the condition of the patient.


Phenytoin; Magnesium Sulphate; Caesarean Section; Eclampsia; Pre-Eclampsia

Full Text:



Heard, A.R., et al., Hypertension during pregnancy in South Australia, part 1: pregnancy outcomes. Australian and New Zealand journal of obstetrics and gynaecology, 2004. 44(5): p. 404-409.

Danmusa, S., et al., Scale-up of magnesium sulfate for treatment of pre-eclampsia and eclampsia in Nigeria. International Journal of Gynecology & Obstetrics, 2016. 134(3): p. 233-236.

Hauth, J.C., et al., Pregnancy outcomes in healthy nulliparas who developed hypertension. Obstetrics & Gynecology, 2000. 95(1): p. 24-28.

Nwanodi, O.B. Preeclampsia-Eclampsia Adverse Outcomes Reduction: The Preeclampsia-Eclampsia Checklist. in Healthcare. 2016: Multidisciplinary Digital Publishing Institute.

Roy, J., J.K. Mitra, and A. Pal, Magnesium sulphate versus phenytoin in eclampsia-maternal and foetal outcome-A comparative study. Australas Med J, 2013. 6(9): p. 483-495.

Sharma, R., et al., Efficacy of Magnesium Sulphate Versus Phenytoin in Seizure Control and Prophylaxsis in Patients of Eclampsia and Severe Pre-eclampsia. 2008.

Euser, A.G. and M.J. Cipolla, Magnesium sulfate for the treatment of eclampsia a brief review. Stroke, 2009. 40(4): p. 1169-1175.

Gordon, R., et al., Magnesium sulphate for the management of preeclampsia and eclampsia in low and middle income countries: a systematic review of tested dosing regimens. Journal of Obstetrics and Gynaecology Canada, 2014. 36(2): p. 154-163.

Duley, L., et al., Alternative magnesium sulphate regimens for women with pre‐eclampsia and eclampsia. The Cochrane Library 2010.

Long, Q., et al., Clinical practice patterns on the use of magnesium sulphate for treatment of pre-eclampsia and eclampsia: a multi-country survey. BJOG: an international journal of obstetrics and gynaecology, 2016.

Duley, L. and A. Gulmezoglu, Magnesium sulphate versus lytic cocktail for eclampsia. Cochrane Database Syst Rev, 2001. 1(1).

Duley, L. and D.J. Henderson‐Smart, Magnesium sulphate versus diazepam for eclampsia. The Cochrane Library, 2003.

Bokslag A, van Weissenbruch M, Mol BW, de Groot CJ. Preeclampsia; short and long-term consequences for mother and neonate. Early Hum Dev 2016; 102:47-50.

Cotton DB, Hallak M, Janusz C, Irtenkauf SM, Berman RF. Central anticonvulsant effects of magnesium sulfate on N-methyl-D-aspartate-induced seizures. Am J Obstet Gynecol 1993;168(3 Pt 1): 974-8.

Hallak M. Effect of parenteral magnesium sulfate administration on excitatory amino acid receptors in the rat brain. Magnes Res 1998; 11(2): 117-31.

Dommisse J. Phenytoin sodium and magnesium sulphate in the management of eclampsia. Br J Obstet Gynaecol 1990;97(2): 104-9.

Roberts JM. Pregnancy related hypertension. In: Creasy RK, Resnik R, editors. Maternal fetal medicine. 4th ed. Philadelphia, PA: WB Saunders; 1998. p.833–72.

Szal SE, Croughan-Minihane MS, Kilpatrick SJ. Effect of magnesium prophylaxis and preeclampsia on the duration oflabor. Am J Obstet Gynecol 1999; 180(6 Pt 1): 1475-9.

Belfort MA, Clark SL, Sibai B. Cerebral hemodynamics in preeclampsia: cerebral perfusion and the rationale for an alternative to magnesium sulfate. ObstetGynecol Surv 2006; 61(10): 655-65.

Lucas MJ, Leveno KJ, Cunningham FG.A comparison of magnesium sulfate with phenytoin for the prevention of eclampsia. N Engl J Med 1995; 333(4):201-5.

Slater RM, Wilcox FL, Smith WD, Donnai P, Patrick J, Richardson T, et al. Phenytoin infusion in severe pre-eclampsia. Lancet 1987; 1(8547): 1417-21.

Robson SC, Redfern N, Seviour J, Campbell M, Walkinshaw S, Rodeck C, et al. Phenytoin prophylaxis in severe pre-eclampsia and eclampsia. Br J ObstetGynaecol 1993; 100(7): 623-8.

Appleton MP, Kuehl TJ, Raebel MA, Adams HR, Knight AB, Gold WR. Magnesium sulfate versus phenytoin for seizure prophylaxis in pregnancyinducedhypertension. Am J Obstet Gynecol 1991;165(4 Pt 1): 907-13.

Unnikrishnan B, Rakshith P, Aishwarya A, Nithin K, Rekha T, Prasanna P, et al. Trends and Indications for cesarean Section in a tertiary care Obstetric Hospital in Coastal South IndiaAustralasMed J 2010; 3(12): 821-5.

Snyman L. Is the high cesarean section rate a couse for concern? Obstetrics and Gynaecology Forum 2002; 12(2): 8-13.

Belfort MA, Anthony J, Saade GR, Allen JC, Jr. A comparison of magnesium sulfate and nimodipine for the prevention of eclampsia. N Engl J Med 2003; 348(4):304-11.

Atkinson MW, Guinn D, Owen J, Hauth JC. Does magnesium sulfate affect the length oflabor induction in women with pregnancy-associated hypertension? Am J Obstet Gynecol 1995; 173(4): 1219-22.

Leveno KJ, Alexander JM, McIntire DD, Lucas MJ. Does magnesium sulfate given for prevention of eclampsia affect the outcome oflabor? Am J Obstet Gynecol 1998; 178(4): 707-12.

Witlin AG, Sibai BM. Magnesium sulfatetherapy in preeclampsia and eclampsia. Obstet Gynecol 1998; 92(5): 883-9


  • There are currently no refbacks.

Creative Commons Attribution-NonCommercial 3.0

This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License which allows users to read, copy, distribute and make derivative works for non-commercial purposes from the material, as long as the author of the original work is cited properly.