MisoprostolTheory & Practice

In Obstetrics

Objectives Be familiar with the nature and

pharmacokinetics of misoprostol.

Establish the difference between different routes of drug adminstration.

Strengthen the self-confidence with erasing the internal worries about the use of misoprostol.

Subjects

Nature & pharmacokinetics of misoprostol.

Adverse reactions. Uses of misoprostol.

Nature

Synthetic PGE1 analog Why?

Pharmacokinetics

Routes of adminstration & absorption:•Oral…..affected by food & antacids•Sublingual•Vaginal•Rectal•Parentral……NO

ORAL VAGINAL

ORALRECTAL

Mainly in the liver……So take care in hepatic patient not renal one.No accumulation.

Metabolism

oDiarrheaoAbdominal painoHeadacheoNausea

oVomitingoFlatulenceoChillsoShiveringofeveroLess common adverse reactionsoDose-dependent

Adverse reactions

2200 g (11 tablets) No serious side effects

Toxicity

Serious side effects:I. HyperthermiaII. RhabdomyolysisIII.HypoxemiaIV.Acid-base balance

disorder

6000 g (30 tablets)

Teratogenicity:

Mobius syndromeCategory “X”

Uses of misoprostol Obstetric uses: Termination of pregnancy 1st trimester 2nd trimester 3rd trimester Postpartum hemorrhage Prevention Treatment Gynecological uses Pre-hysteroscopy Intauterine Insemination (IUI) Cervical pregnancy GIT Prevention & treatment of peptic ulcer induced by NSAIDs

Misoprostol in 1st trimester

mifepristone

misoprostol

methotrexate

misoprostol

misoprostol

3 different regimens

success

91-97% 88-100% 47% ????

Gestational age not more than 49 days (completed 7 weeks)

6 hr 36-48hr 5-7 days

Gestational age more than 56 days (completed 9 weeks)

Misoprostol as cervical –priming agent before vaccum-aspiration of the products of conception

400 g vaginal 3 hours before procedure

Misoprostol PGE2

Misoprostol in 2nd trimester

Misoprostol 400 g vaginal every 3 hours

Misoprostol = PGE2 = extraamniotic PGs

Misoprostol in 3rd trimester

Induction of labor

Living fetus at term Dead fetus at term

Misoprostol 25 g every 6 hours

Misoprostol 50 g every 12 hours

why?

Concerns about misoprostol in induction of labor !!!!!

Uterine tachysystoleUterine hyperstimulationUterine rupture

Misoprostol in postpartum hemorrhage (PPH)

Prevention of PPH Treatment of PPH Insufficient evidence to support its routine use

when oxytocin or methyl-ergometrine

is available

Rectal misoprostol 800 g

Useful 1st line drug for ttt PPH

Why ?

WHO misoprostol multicenter Trial concluded that oral tablets of 600 g was associated with

a higher risk of:

Severe postpartum hemorrhageNeed for additional uterotonicsShivering Pyrexia

This is in comparison to intramuscular or intravenous oxytocin

But Why misoprostol is still evaluated as uterotonic

agent despite its side-effects

1)Ease of use2)Stability in field conditions3)Longer shelf-life4)Less expense

Thank you for your attention!

Any Questions?

Mohamed Gamal Saleh Ibrahim

e-mail: mgs_medicine@hotmail.commobile:002 012 630 1515