Common drugs in Obstetrics Flashcards
What are the indications for Oxytocin ?
- Induction and augmentation of labor
- Control and prevention of PPH
- Controls bleeding after: abortion or D & C for molar pregnancies
What are the contraindications for Oxytocin?
- Uterine scar
- Multiple pregnancies
- Fetal distress
- Malpresentation
What are the side effects of Oxytocin?
- Uterine Hyperstimulation
- Uterine rupture
- Maternal hypotension
- Fetal hypoxia and death
What are the MOA of Oxytocin?
MOA - Mechanism of action
In the Uterus: promotes uterine contractions by binding to oxytocin receptors in the myometrium → depolarization of muscle fibers and influx of Ca 2+ ions. Concentration of oxytocin receptors increases significantly in the 3rd trimester
In the Breast: facilitates milk ejection reflex via myoepithelial cell contraction
what is the brand name for Oxytocin?
Pitocin
What is Misoprostol?
A Prostaglandin E1 (PGE1) analog
What is the brand name of Misoprostol?
Cytotec
What is the MOA for Misoprostol?
MOA - Mechanism of action
Promotes uterine contractions & cervical ripening
What are the indications for Misoprostol?
- Control PPH
- Cervical ripening & induction
- Medical abortions
- Prophylaxis for NSAID-induced gastric ulcers (contraindicated during pregnancy)
What are the contraindications of Misoprostol?
- Treating of gastric ulcers while pregnant
- Uterine scar
- Hypersensitivity reaction
What are the side effects of Misoprostol?
- Nausea & Vomiting
- Diarrhea
- Uterine Hypertimulation
- Meconium stained liqour
What is the brand name of Methylergometrine?
Methergine
What is the MOA of Methylergometrine?
induces rapid and sustained tetanic uterine contractions by binding to Dopamine D1 receptors
What are the indications of Methylergometrine?
- Prevention & control of PPH
- Facilitate uterine contractions after C-section
- Control bleeding after: abortion and D & C for molar pregnancy
What are the contraindications for Methylergometrine?
- Administration after delivery of 1st twin (→ entrapment of 2nd twin)
- Heart disease (causes pulmonary edema due to sequestration of blood from uterine circulation into systemic circulation)
- Pre-eclampsia & Eclampsia (causes a sudden rise in BP)
What is the brand name for Carbopost tromethamine?
Hemabate
What is the MOA for Carbopost tromethamine?
Promotes uterine contraction
What are the indications for Carbopost tromethamine?
- Treat PPH 2° Uterine Atony
- 2nd Trimester termination
What are the contraindications to Carbopost tromethamine?
Use with caution in patients with:
* Asthma
* HTN
* Hepatic or Renal disease
What are the side effects to Carbopost tromethamine?
- Nausea & Vomiting
- Diarrhea
- Bronchoconstriction
- HTN
- Headache
- Flushing
- Pyrexia
What is Mifeprestone?
An antiprogesterone (i.e., progesterone) & glucocorticoid antagonist
What is the MOA for Mifeprestone
Because of it’s antiprogesterone effect it:
1. Prevents implantation of zygote
2. Prevents further development of implanted embryo
What are the indications Mifeprestone?
- Medical abortion
- Emergency contrception
- Treat Fibroids & Endometriosis
What are the contraindications for Mifeprestone?
- Ectopic pregnancy
- Bleeding disorders
- Anticoagualnt thereapy
- Long term corticosteroid therapy
- Adrenal failure
- Inherited porphyrias
What are the side effects of Mifeprestone?
- Nausea & Vomiting
- Bleeding & Lower abdominal cramps
What is MgSO4
Magnesium sulfate (MgSO4)
A Tocolytic
What is the MOA for MgSO4
Magnesium sulfate (MgSO4)
- MgSO4 is a tocolytic, competes with Ca2+ ions for entry into the myometrium
- Blocks NMDA receptors in the brain
- reduces:
* motor end plate sensitivity to ACh
* the release of ACh from nerve endings
N-methyl-D-aspartate (NMDA)
Acetylcholine (ACh)
What are the indications for MgSO4?
- Prevent convulsions in severe Pre-eclampsia & imminent eclampsia
- Anticonvulsant in eclampsia
- Preterm labor
- Neuroprotective effect on fetus
What are the contraindications of MgSO4?
- Myasthenia gravis
- Maternal renal disease
What are the side effects of MgSO4?
- Respiratory depression
- Respiratory & neuromuscular depression of newborn if mother recieved MgSO4 for prolonged periods prior to delivery
- Muscle weakness
- reduced FHR variability
What is the antitode for MgSO4?
Calcium gluconate:10mL in 10% solution IV slow push
What is the brand name for Methyldopa?
Aldomet
What are the indications for Methyldopa?
BP control in Pre-eclampsia & Eclampsia
What are the side effects of Methyldopa?
Maternal:
1. Postural hypotension
2. Bradycardia
3. Sedation
4. Headache
5. Depression
6. Hemolytic anemia
7. Hepatitis
Fetal: Intestinal illeus
What is the brand name for Labetalol?
Trandate
What is Labetalol?
A combined Alpa & Beta adrenergic receptor blocker
What is the MOA of Labetalol?
Reduces peripheral vascular resistance & lowers BP
What are the indications for Labetalol?
- Pre - eclampsia
- Eclampsia
- HTN ° Pheochromocytoma
- Clonidine withdrawal
What are the contradications of Labetalol
- Asthma
- Heart block
- CHF
- Cardiogenic shock
what are the side effects of Labetalol?
- Postural HTN
- Bronchospasm
- CHF
- Tremors
- Headache
What is the MOA for Nifedipine
inhibits the voltage gated L-type calcium channels on vascular smooth muscle & myocardial cells → arteriolar vasodilation
What are the indications for Nifedepine?
- Pre - eclampsia
- Tocolysis in Preterm Labor
What are the side effects of Nifedipine
- Hypotension
- Tachycardia
- Headache
- Tocolysis
- DO NOT use with MgSO4
What is the brand name for Butylscopolamine?
Buscopan
What is another name for Butylscopolamine?
Hyoscine butylbromide
