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Flashcards in OB Pharmacology Deck (60)
1

What should we treat spontaneous abortion with?

Misoprostol (Cytotec)

2

SPONTANEOUS ABORTION: Products of conception are evacuated in 3 ways?

1. Surgical
Unstable, significant bleeding, infection or want immediate treatment

2. Medical
Those who do not want to wait for spontaneous passage

3. Expectant
Will eventually pass naturally (days to weeks)

3

MISOPROSTOL IS THE MAIN DRUG FOR MEDICAL MANAGEMENT
1. MOA?
2. For which type of abortions? 2
3. Off label use? 2

1. Prostaglandin E1 analog and induces uterine contractions
2.
-For missed abortion
-For incomplete abortion

3. Unlabeled uses
-Cervical ripening (intravaginally)
-Treatment of post partum hemorrhage


4

PRETERM LABOR
What drugs should we use? 2

1. Tocolytics
2. Corticosteroids

5

GOALS OF TOCOLYTICS
3

1. Delay delivery by at least 48 hours to allow the administration of corticosteroids for fetal lung maturity

2. Provide time for transport of the mother to a higher level of care

3. Stop labor to allow the underlying medical condition that stimulated labor to clear

6

BENEFITS OF TOCOLYTICS NEED TO OUTWEIGH THE RISKS
1. Used on what timeline?
2. Contraindications? (main one?)
9

1. Generally not used past 34 weeks of gestation and controversial use any earlier than 22 weeks

2.
-Contraindicated when the baby or the mother are unstable**
Review of contraindications
-Fetal demise,
-lethal fetal anomaly,
-nonreassuring fetal status,
-severe preeclampsia or
-eclampsia,
-maternal hemorrhage,
-intraamniotic infection,
-maternal contraindication to the tocolytic drug

7

WHAT IS THE DOC AT 24-32 WEEKS GESTATION for preterm labor?

INDOMETHACIN

8

INDOMETHACIN
1. MOA?
2. Maternal SE? 5

1. Decreases prostaglandin production through inhibition of cyclooxygenase

Maternal side effects
1. Nausea,
2. GE reflux,
3. gastritis,
4. emesis
5. Platelet dysfunction

9

1. FETAL SIDE EFFECTS OF INDOMETHACIN

2. Neonatal complications associated with use? 5

1.
-Constriction of ductus arteriosus
-Oligohydramnios

2.
-Bronchopulmonary dysplasia,
-necrotizing enterocolitis,
-PDA,
-periventricular leukomalacia,
-intraventricular hemorrhage
Data is conflicting

10

INDOMETHACIN
1. Constriction of ductus arteriosus if drug is given when?
2. More likely to occur in what gestational week?

3. What is Oligohydramnios?

1. If drug given > 48 hrs
2. More likely to occur past 32 weeks

3. Drug decreases fetal urine output therefore decreasing amniotic fluid volume

11

INDOMETHACIN
1. Maternal contraindications? 6

2. Monitoring: If given > 48 hours then need what?

1. Maternal contraindications
-Platelet dysfunction
-Bleeding disorders
-Hepatic dysfunction
-GI ulcers
-Renal dysfunction
-Asthma if also sensitive to ASA


2. fetal US to evaluate for oligohydramnios and narrowing of the ductus arteriosus

12

What is second line therapy for preterm labor?

NIFEDIPINE FOR SECOND LINE THERAPY

13

1. NIFEDIPINE MOA?
2. Associated with what?
3. Maternal SE? 6

1. Calcium channel blocker which results in myometrial relaxation and peripheral vasodilation

2. Associated with fewer maternal side effects compared to magnesium sulfate

3. Maternal side effects
-Nausea,
-flushing,
-headache,
-dizziness,
-palpitations
-Can cause severe hypotension

14

NIFEDIPINE
1. Contraindications? 4

2. Precaution? 1

1. Contraindications
-Hypotension,
-preload dependent cardiac lesion,
-use cautiously in LV dysfunction -CHF

2. Precaution
Do not use in conjunction with magnesium sulfate as they can act synergistically to suppress muscle contraction and result in respiratory depression

15

NIFEDIPINE PHARMACOKINETICS
1. Half life?
2. Peak plasma concentration?
3. Metabolized and excreted through what?

1. Half life 2-3 hours

2. Peak plasma concentrations in 30-60 minutes

3. Metabolized through the liver and excreted by the kidneys

16

32-34 WEEKS GESTATION (preterm labor)
1. DOC?
2. Second line?

3. Maternal SE? 8

1. Nifedipine is the DOC

2. Second line therapy is a Beta-adrenergic receptor agonist
-Terbutaline is the most commonly used in the US

3. Maternal side effects
-Tachycardia,
-palpitations,
-hypotension,
-tremor,
-shortness of breath,
-chest discomfort,
-hypokalemia,
-hyperglycemia

17

BETA ADRENERGIC RECEPTOR AGONISTS
-Contraindications? 3
-Do not use longer than what?

Contraindications
1. Tachycardia sensitive cardiac disease
2. Uncontrolled hyperthyroidism or DM
3. Use with caution in placenta previa or abruption due to risk of hypovolemia and shock

1. Do not use longer then 48-72 hours

18

MONITORING in preterm labor?
4

1. I/O’s
2. Maternal symptoms of shortness of breath, CP, tachycardia
3. Stop drug if maternal HR > 120
4. Check blood glucose and K+ every 4-6 hours

19

OTHER TOCOLYTICS
Third line treatment?

Magnesium sulfate

20

CORTICOSTEROIDS
Reduces the incidence of the following by 50%?
5

1. respiratory distress syndrome
2. intraventricular hemorrhage
3. necrotizing enterocolitis
4. sepsis
5. neonatal mortality

21

ANTENATAL CORTICOSTEROIDS
1. Used in which weeks?
2. Whats preferred?
3. Other option?

1. 23-34 weeks

2. Betamethasone (preferred)
12 mg IM q 24 hrs X 2

3. Dexamethasone (use non-sulfite containing suspension otherwise neurotoxicity of fetus)
6 mg IM q 12 hrs X 4

22

INDICATIONS FOR ABX PROPHYLAXIS for Group B strep
4

1. Positive rectovaginal culture

2. Positive history of birth of an infant with early onset GBS disease

3. GBS bacteriuria during current pregnancy

4. Unknown culture status AND
-Maternal fever ≥ 100.4 OR
-Preterm labor less than 37 weeks OR
-Prolonged rupture of the membranes ≥ 18 hours

23

GROUP B STREP
Don’t give abx prophylaxis for GBS positive patient undergoing what?

planned c-section unless their membranes rupture

24

ANTIBIOTIC REGIMEN
Group B Strep? 2

1. Penicillin G
5 million U IV then 2.3-3 million U q 4 hours until delivery

2. OR Ampicillin
2 g IV followed by 1g q 4 hours until delivery

25

ANTIBIOTIC REGIMEN
Group B Strep for PCN allergic pts:

1. Low risk for anaphylaxis?

2. High risk for anaphylaxis to PCN then use? 2

PCN allergic patients

1. Cephazolin (Ancef) 2g IV then 1g q 8 hours until delivery

2.
-Clindamycin (if known to be susceptible)
-OR Vancomycin 1g IV q 12 hours until delivery

26

PREMATURE RUPTURE OF THE MEMBRANES: ANTIBIOTIC PROPHYLAXIS
1. What may be the cause of the premature rupture? 2

2. Tx? 3

3. If PCN allergy? 3

1.
-Infection may be the cause of the premature labor or may be a
-consequence of premature rupture of the membranes

2.
-1g azithromycin on admission
-Followed by ampicillin 2 g IV q 6 hr X 48 hrs
-Followed by amoxicillin 875mg BID X 5 days

3. If PCN allergy
-Clindamycin 900 mg IV q 8 h X 48 h
-+ gentamycin 7 mg/kg IBW q 24 h X 2
-Followed by Clindamycin 300 mg q 8 h X 5 days

27

ADDITIONAL MEDICAL THERAPY: for premature membrane rupture?
2

1. Tocolytics are often given to delay delivery in the presence of uterine contractions

2. Corticosteroids may be indicated

28

POSTPARTUM HEMORRHAGE
Which drugs to use?
4

1. Oxytocin
2. Misoprostol
3. Carboprost tromethamine
4. Methylergonovine maleate

29

POST PARTUM HEMORRHAGE UTEROTONIC DRUGS
1. DOC?
2. Then add? 3

1. Oxytocin is the uterotonic DOC
2.
-Add Misoprostol
-Add Methylergonovine
-Add Carboprost tromethamine (Hemabate

30

POST PARTUM HEMORRHAGE UTEROTONIC DRUGS

OXYTOCIN
1. Administered how?
2. If already on an infusion do what?

3. If no IV access do what?

1. 40 U in 1 L saline infuse at 10-40 ml/min
2. increase the dose
3. give 10 U IM

31

POST PARTUM HEMORRHAGE UTEROTONIC DRUGS

MISOPROSTOL (CYTOTEC)
1. MOA?
2. Peak concentration?
3. Adverse reactions? 2

1. Synthetic prostaglandin that stimulates uterine contractions


2. Peak concentration 30 min post SL, 40-60 min post PR

3. Adverse reactions
-GI – diarrhea, abd pain, constipation, dyspepsia, flatulence, N/V
-CNS - Headache

32

POST PARTUM HEMORRHAGE UTEROTONIC DRUGS

METHYLERGONOVINE (METHERGINE)
1. Class of drug?
2. MOA?
3. Administered?
4. Dont give how?
5. Contraindicated? 3

1. Ergot alkaloid
2. Acts directly on the smooth muscle and increases uterine tone and strength and frequency of contractions

3. 200 mcg IM or intramyometrial
Q 2 h up to 5 doses

4. Do not give IV

5. Contraindicated
-HTN,
-Raynaud’s,
-Scleroderma

33

POST PARTUM HEMORRHAGE UTEROTONIC DRUGS

CARBOPROST TROMETHAMINE (HEMABATE)
1. Delivered how?
2. Max dose?
3. Peak plasma concentration?
4. Do not give how?
5. Contraindicated in who? 4

1. 250 mcg IM Q 15-90 min prn
2. Max dose 2 mg (8 doses)
3. Peak plasma concentration 30 min
4. Do not give IV
5. Contraindicated in
-asthma,
-HTN,
-renal failure and
-reduced cardiac output

34

PREECLAMPSIA
SEVERE HTN DURING LABOR
Which meds? 3

1. IV labetalol
2. Or IV hydralazine
3. Or PO nifedipine

35

SEIZURE PROPHYLAXIS WITH what?

MAGNESIUM SULFATE

36

1. All cases of preeclampsia should be treated with magnesium sulfate during labor to prevent _______?

2. Seizure prophylaxis with magnesium sulfate does not prevent what?

1. seizures


2. the progression of preeclampsia

37

MAGNESIUM SULFATE
1. Adjust dose with what?
2. Continue for ___ hours after delivery

3. MOA?

4. Normal magnesium plasma levels are ______ mEq/L

1. renal insufficiency

2. 24

3. blocks neuromuscular transmission and decreases the amount of acetylcholine at the end plate of the motor neuron impulse


4. 1.5-2.5

38

ADVERSE EFFECTS OF ELEVATED MAGNESIUM LEVELS
1. Plasma level 4 mEq/L?

2. Plasma level of 8-10 mEq/L?

3. Plasma level 10-15 mEq/L?

4. Plasma level 20-25 mEq/L?

5. What should we do to treat toxic levels of magnesium?

1. Deep tendon reflexes decrease

2. Deep tendon reflexes absent

3. Respiratory Paralysis

4. Cardiac arrest

5. Calcium gluconate 1 g IV over 10 min to

39

MAGNESIUM SULFATE
1. Blood levels checked q 4-6 hours to maintain therapeutic level (_______ mEq/L)?

2. Other side effects? 6

3. Contraindications? 3

4. Do not use in conjunction with a what?

1. 4.8-8.4

2.
-flushing, diaphoresis, warmth,
-nausea, vomiting,
-headache,
-muscle weakness,
-visual disturbance,
-palpitations

3.
-heart block,
-myocardial damage,
-myasthenia gravis

4. calcium channel blocker

40

Induction of labor DOC?

Oxytocin (Pitocin)

41

OXYTOCIN (PITOCIN)
1. MOA? 2
2. Contraindications?

1.
-Stimulates uterine contractions by activation of G-protein-coupled receptors that trigger increased intracellular calcium levels

-Also increases prostaglandin production

2. Contraindications are basically conditions in which you would want to avoid vaginal delivery

42

OXYTOCIN ADVERSE REACTIONS: Maternal?
4

1. CV – arrhythmias, HTN
2. GI – nausea, vomiting
3. GU – pelvic hematoma, postpartum hemorrhage, uterine hypertonicity, uterine rupture

4. Severe water intoxication with seizure, coma and death associated with a slow infusion over 24 hours

43

OXYTOCIN ADVERSE EFFECTS
Fetal?
5

1. CV – arrhythmia, bradycardia
2. CNS – brain damage, seizures
3. Hepatic - jaundice
4. Ocular – retinal hemorrhage
5. Other – death, low Apgar score

44

COMMON DISORDERS with OB Pharm? 5

1. Diarrhea
2. Constipation
3. GERD
4. Cough and cold symptoms
5. Analgesics

45

DIARRHEA
Tx?
3

1. Oral rehydration and
2. dietary changes are best and

3. loperamide should only be used in small amounts and ONLY if symptoms are disabling and conservative measures have not worked

46

CONSTIPATION
1. First line?
2. Second line?
3. What are the drugs in this category? 4

1. First line increase dietary fiber and fluids

2. Bulk forming laxatives are the preferred treatment as they are not absorbed

3.
-Psyllium (Metamucil)
-Methylcellulose (Citrucel)
-Calcium polycarbofil (Fibercon)
-Wheat dextrin (Benefiber)

47

CONSTIPATION
Treatment of refractory cases for occasional use
3


What should we avoid and why? 2

Minimal absorption
1. Lactulose - category B
2. Bisacodyl (Dulcolax) generally considered safe
3. Magnesium hydroxide (Milk of Magnesia)
Magnesium crosses the placenta but is determined to be safe


AVOID
1. Castor oil – stimulates contractions
2. Mineral oil – interferes with vitamin absorption

48

GERD: Tx?
4

1. Lifestyle modification
2. Sulcralfate 1g po TID is the preferred agent after failure of lifestyle and antacids
3. H2 receptor blockers
4. PPIs

49

GERD
1. What kind of lifestyle modifications are good for this? 3

2. If failure of what use H2 blockers?

3. Which ones? 2

4. Which PPIs would you use? 3

1.
-Elevation of the head of the bed,
-dietary modification,
-antacids prn

2. If failure of Sulcralfate then

3.
-Ranitidine (Zantac) or
-Cimetidine (Tagamet) both PG category B

4.
-Lansoprazole (Prevacid) (cat B)
-Pantoprazole (Protonix) (cat B)
-Omeprazole (Prilosec) (cat C)

50

COLD SYMPTOMS
Tx?
5

1. Heated, humidified air for congestion symptoms
2. Acetaminophen for sore throat, fever or headache
3. Saline nasal spray or irrigation
4. Ipatropium bromide (Atrovent) nasal spray for Rhinorrhea
5. (Pseudoephedrine (Sudafed) AVOID in 1st trimester - single doses in 3rd trimester don’t seem to have long term effects except for fetal tachycardia)- Nasal congestion

51

COUGH SUPPRESSANT
Rx?
3

1. Inhalation of warm, humidified air

2. Dextromethorphan (Robitussin)
Category C
3. Guaifenesin (Mucinex)
Category C

52

ANALGESICS
1. Cat?
2. Small but statistically significant correlation between acetaminophen use during pregnancy and what in offspring?

3. May also be associated with what in early childhood?

4. Still the DOC for what?

Need to weigh the risks and benefits when treating fever

1. C
2. ADD behavior

3. wheezing and asthma

4. maternal pain and fever

53

ANALGESICS
1. ______ should be avoided
2. Prior to 30 weeks category __?
3. Close to conception may cause what?
4. Other complications that may result? 2

5. After 30 weeks category___?
-why?

1. NSAIDs

2. C

3. miscarriage

4.
-Cardiovascular anomalies
-Cleft lip/palate

5. D
-Premature closure of the ductus and all kinds of other significant abnormalities

54

DRUGS THAT STIMULATE OVULATION
2

1. Clomiphene (Clomid)
2. Metformin (Glucophage)

55

CLOMIPHENE (CLOMID)
1. Class of drug?
2. MOA? 5

1. Class: Ovulation stimulator, selective estrogen receptor modifier

2.
-Inhibits normal estrogenic negative feedback
-Impairment of the feedback signal results in increased pulsatile GnRH secretion from the hypothalamus
-(FSH, LH) release
-Which leads to growth of the ovarian follicle
-Followed by follicular rupture

56

CLOMIPHENE (CLOMID)
1. Start on which day of the mentrual cycle?
2. Timing of intercourse should be when?
3. Dose adjustment?

1. Start the 5th day of the menstrual cycle
2. Timing of intercourse 5-10 days after completion of the 5 day course

3. Dose adjustment
Subsequent doses may be increased to 100 mg once daily for 5 days only if ovulation does not occur at the initial dose

57

CLOMIPHENE (CLOMID)
1. If we need a repeat course when should we do it?
2. Exclude what before we start?
3. What dose should be used?

Repeat courses
1. If needed, the 5-day cycle may be repeated as early as 30 days after the previous one
2. Exclude the presence of pregnancy
3. The lowest effective dose should be used

58

CLOMIPHENE (CLOMID)
1. Max dose?

2. Discontinue when?

1. 100 mg once daily for 5 days for up to 6 cycles

2. Discontinue if ovulation does not occur after 3 courses of treatment; or if 3 ovulatory responses occur but pregnancy is not achieved.


59

METFORMIN (GLUCOPHAGE)
1. Class?
2. Associated with what? 3
3. Compare the live birth rate with Metformin?
4. In addition to hormonal benefits by its insulin it may also help with what?

1. Class: Biguanide
2. Associated with
-increased menstrual cyclicity
-improved ovulation
-reduction in circulating androgen levels

3. Live birth rate is not as high as that with clomid

4. In addition to hormonal benefits by its reduction in insulin, it also may help stimulate weight loss

60

PATHOPHYSIOLOGY
1. PCOS patients may be what?

2. Insulin stimulates ovarian what?

3. Suppresses the what of sex hormone-binding globulin?

4. The increased intraovarian androgens then disrupt what?

5. _____________ may also directly cause premature follicular atresia and antral follicle arrest

6. The resulting anovulation also leads to unopposed estrogen production and endometrial proliferation in women with PCOS, leading to an increased risk of what?

1. insulin resistant

2. theca cell androgen production and secretion

3. hepatic production

4. folliculogenesis

5. Hyperinsulinemia

6. endometrial hyperplasia