Pharmacotherapeutics in obstetrics

Pharmacotherapeutics in Obstetrics for B.Sc. Nursing students
Here the drugs used during pregnancy, labor and during puerperium are explained.

1. PHARMACOTHERAPEUTICS IN OBSTETRICS

2. 3

3. nonapeptide

4. tetanic

5. a 7 Pr Pi

1. Megaloblastic or macrocytic anemia
during pregnancy to prevent fetal damage
2. Prevent fetal neural tube defect during
pregnancy

Contraindications
1. untreated vitamin B12 deficiency.

6. 1. Abdominal cramps
2. Diarrhoea

3. Rash

4. Irritability

5. nausea or bloating

D route cfadmint 5

0.4mg or 400mcg OD orally
0.4-0.8mg IM Or subcutaneously daily.

7. 1. Patient with H/O fetal neural tube defect
in pregnancy should increase folic acid
intake 1 month before and 3 months after
conception.

2.Patient with intestinal malabsorption
may need parentral administration.

8. = =

Preparation

Each 100mg provides 33mg of elemental iron.
Tablet- 90mg,200mg,300mg,325mg,350mg

Action

Provides elemental iron, an essential component
in the formation of haemoglobin!

ーー ーー コ

9. 1. Iron deficiency
2. As a supplement during pregnancy

Contraindications

1. Primary haemolytic anemia
2. Peptic ulcer disease

3. Ulcerative colitis

4. Repeated blood transfusions

“A

10. 8- Nausea or vomiting ト
4. Gl irritation ‘ =>
5. Black stools SS

O430mg OD orally

Olnjection- 20mg elemental iron/ml in 5ml and 10m!
single dose vial (iron sucrose )

ODose-15mg/kg body weight or max 1000mg in single Inj
IM Or diluted with 100ml of NS for IV.

11. 4. Advised patient to avoid taking tablet with
milk or along with antacids.
2. Caution patient to crush tablet
3. Caution patient not to substitute one iron salt
for another because amount of elemental iron
may vary.
4. Advised patient to report for constipation or
change in stool colour

12. ‘each tablet contains 211mg or 10.6meq of
elemental calcium

tablet- 250mg, 500mg

Action
Replaces calcium and maintain calcium level

Ba
- 2
supplement

13. 3Renal calculi

Adverse effects

1. Headache

2. Irritability
3.Hypercalcemia
4.Chalky taste

5. Nausea or vomitings

ndr E ministration
500mg OD orally.

14. = ~ » dE
1.Advise patient to take oral calcium 1 or
1.5 hours after meals if Gl upset occurs
2. Monitor calcium level if the patient is
having mild renal impairment.
3. Advise patient to report for any kind of
abdominal pain, vomiting or nausea
occurs.

15. ® Here Gre the choice of drugs given during
pregnancy are:-

1. Alpha and Beta blockers- Labetalol
hydrochloride
2. calcium channel blockers-Nifedipine
3.alpha blockers-Methyldopa
4.vasodilators-Hydralazine hydrochloride—

— =

16. re

= »
"These drugs should be avoided because they
may can cause poor fetal renal function,
malformation or can cause IUGR

1.ACE inhibitors

2. Minoxidil

3. Sodium Nitoprusside
4. Diltiazem

5. Atenolol
6.Propranolol

17. u Preparatton
Ulnjection-5mg/ml in 2omI vial
OTablets- 100mg,200mg ,300mg

Action
Reduced peripheral vascular resistance as a
result of alpha and beta blockade.

18. 1.Hype:
W 2. Hypérténsive emergencies

ntraindi ion
1.Hypersensitive to drug or its component.
2.Bronchial asthma
3.Hepatic or heart failure
4.Prolonged hypotension
5.Severe bradycardia

19. 1. Diz.

を Fatigue >
. Nausea or vomiting

4. Headache

5. Vertigo

Dosage and route of administration
50mg or 100mg tablet OD orally

20mg/20ml Inj IV bolus wait for 10min if no response
then give 40mg slow bolus.

20. =

"1: Advised patient to remain in supine position
for 3hrs after infusion.

2. Monitor BP frequently

3. In diabetic patient monitor glucose level
closely.

4. Advised patient that dizziness can be
minimized by rising slowly and avoiding sudden
position change

21. Pr
Capsule-10mg,20mg
Tablet-20mg,30mg,60mg,90mg

Action
Thought to inhibit calcium ion reflex across
cardiac and smooth muscle cells, decreasing

contractility and oxygen demand and also dilates
arteries and arterioles.

22. Indications

4, Hypertension ーー

2. O ——— angina pe —

1.Heart failure
2. Hypotension
3. Severe GI narrowing

Adverse effects
1. Dizziness

2. Syncope

3. Heart failure

4. Muscle cramps
5. Peripheral edema

23. 1. Monitor BP & HR regularly

2. Advise patient to avoid taking this drug with
grapefruit juice.

3. Watch for symptoms for heart failure.

4. Advise patient if chest pain worsen
immediately report to doctor.

24. Preparations

OTablet-250mg,500mg
Olnj-50mg/mi

Action

Inhibit the central vasomotor centre, decreasing
sympathetic outflow to the heart, kidney and
peripheral vasculature

25. ntraigdieations —
1. Hepatic disease or liver cirrhosis
2. Lactating mother

Adverse effects f
1. Decrease mental acuity

2. Sedation o
3. Headache or depression

4. Bradycardia

5. Hepatic necrosis

6. Hepatitis

26. 25

w ~ »
Nur: nsider 위 E N A
1. Mo or BP regularly. 28
2. Monitor patient coomb's test result. = ~
3. Report for involuntary movements.

4.Tell patient to check weight daily and notify if he gains
2 or more pounds in a week

27. Olnj-20mg/ml in 1ml vial
OTablet-10mg,25g,50mg,100mg

Action
Direct acting peripheral vasodilator that relexes arteriolar
smooth muscle.

Indi ion:
1. Hypertension
2. Severe essential hypertension

28. eE Rheumatic
a Stroke
4. Severe renal impairment

Adverse effects

1. Neutropenia

2. Leukopenia
3.Thrombocytopenia

4. Orthostatic hypotension

29. 25
BD

Smg diluted in 10m1iof NS. slow IV at 15-20minutes
interval.

Nursin nsideration: >.
1. Monitor patient BP, pulse rate, body weight trequently.
2. Monitor patient for muscle and joint pain, fever or
throat pain.

3. Advised patient to take drug after food to increase
absorption

30. “Diuretits Gre used in the following conditions
during pregnancy:
“Sr =
. PIH with massive edema ング
. Eclampsia with pulmonary ederr ^
. Severe anemia in pregnancy with heart failure

1
고
3
4. Prior to blood transfusion in severe anemia
5
d

.As an adjunct to certain antihypertensive
rugs.

31. Preparation
© Omj-10mg9/mi
OTablets-20mg,40mg,80mg,500mg

Action
Inhibits sodium and chloride reabsorption at proximal
and distal tubules and loop of Henle.

Indications

1. Acute pulmonary edema
2. Edema

3. Hypertension

Furosemide
SP

32. 1. Anu
2. Hepat ciprhosis
w3. Allergic to sulfonamides

Adverse effects
1. Maternal: Weakness, fatigue, muscle cramps, hypokalemia

2. Fetal: May occur due to decreased leading to fetal compromise,
hyponatremia.

Dosage and routes of administration
040 mg tablet, daily following breakfast.

U In acute conditions, the drug is administered parenterally in
doses of 40-120 mg daily.

33. iF = _

「 】 ~ | Le
Le Monitor weight, BP and pulse rate routinely
for long term use.
2. Monitor patient I/O chart.
3. Watch the signs for hypokalemia such as
muscle weakness and cramps.
4. Monitor uric acid if patient is having gout.
5. Advise the patient to take drug in the morning
after food.

6. Advised patient to avoid direct sunlight to
prevent photosensitivity reactions.

34. w These drugs can inhibit uterine contractions &
used to prolonged the pregnancy. In women
who develop premature uterine contractions, in
addition to putting them to absolute bed rest &
sedating, Tocolytic drugs are administered in
an attempt to inhibit uterine contraction.

Here are the drugs used are:-
1. Isoxsuprine Hydrochloride
2. Ritrodrine hydrochloride

35. Preparation
WiTablet Foms
Dlnj-10mg/mi

Action

Acts directly on vascular smooth muscle, causes cardiac
stimulation & uterine relaxation And thus causing relaxing the veins
and arteries and making them wider to increase the blood flow to
certain parts of the body.

Isoxsuprine ER
Indication ep oer
1. Prevent Preterm labour een ~,
2. Inhibit uterine contractions. a

Solvay Pharma
India Limited

36. OTo contin
@Mainténafite: IM 10mg 6 hourly for 24 hrs or tab 10mg 6-

8hrly.

Nursing considerations &
1. Assess patient BP, pulse during treatment も
2.Take BP lying & standing as orthostatic hypotension is
common

3. Monitor for Intensity & length of uterine contractions and
FHS.

4. Advise patient to make posi
fainting may occur.

on changes slowly as

37. Oinj-5mi amp-4pmg/mi=50mg per amp.
Tablet-10mg

Action

Acts directly on vascular smooth muscle. causes cardiac stimulation &
uterine relaxant.

indications

Prevent preterm labour

indicati

1. Hypersensitivity
2. Eclampsia

3. Hypertension

4. Dysrhythmias

38. 2. Headache

w3- Restlessness or sweating
4. Chills and drowsiness

5. Nausea or vomiting

6. Altered maternal & fetal heart tone & palpitations.

Dosage and routes of administration

Qinitial: IV drip 100 mg in 5% dextrose @ 0.1 mg/minute gradually
increased by 0.05mg/min ,To continue for at least 2 hrs after
contractions cease.

OMaintenance -Tab 10mg 6-8 hourly PO 10 mg given half hour
before termination of iv, then 10 mg q2 hr x 24 hrs, then 10-20 mg
q4th, not to exceed 120 mg/day

39. 1. Assess. Ma g infusion
w and alSo Ifitensity & length of uterine contractions

2. Monitor Fluid intake to prevent fluid overload,

discontinue if this occurs.

3. Administer only clear solutions after dilution 150 mg

in 500 mi D5W or NS, give at 0.3 mg/ml By Using

infusion pumps/monitor carefully

4. Positioning of patient in left lateral recumbent

position to decrease hypotension & increase renal

blood flow.

5. Advise patient to remain in bed during infusion.

40. 1.Oxytocics

2. Analgesics

3. Anticonvulsant
4. Anticoagulant

41. w Oxytociés are the drugs that have the power to
excite contractions of the uterine muscles.
Among a large number of drugs belonging to
this group the ones that are important and
extensively used are :-
1. Oxytocin
2. Ergot derivatives
3. Prostaglandins

42. Oxytocin is 5
= stored in theposteder pituitary.

Preparations

Synthetic oxytocin available for parenteral use includes:-
*Syntocinon : 5units/ml in ampoules of 1 mi

*Pitocin 10 units/ml in ampoule of 0.5 mi

*Syntometrine : A combination of syntocinon on 5 units &
ergometrine 0.5mg

"Oxytocin nasal solution 40 unit/ml

Actions

Acts directly on myofibrils producing uterine contractions ®

stimulates milk ejection by the breasts

us and

=

{ @

ve

f

43. Pregnan EY"

@.To indd@ aBortion, labour
2.To expedite expulsion of hydatidiform mole
3. For oxytocin challenge test

4.To stop bleeding following evacuation.

La r
1.To augment labour, in uterine inertia
2. to prevent & treat postpartum hemorrhage

Postpartum
1.To initiate milk let-down in breast engorgement.

44. 1. Grand mu ra

3. Contracted pelvis

3. History of LSCS or hysterectomy
4. Malpresentation

During labour

1. All contraindications mentioned in pregnancy
2. Obstructed labour
3. Incoordinate uterine action

Anytime

1. Hypovolemic state, cardiac disease

45. Ww. Uteriffe rúpture

4. Hypotension

5. Neonatal jaundice

6. Water retention 3. water intoxication

Dosage & routes of administration

AControlled IV infusion ( 10 units of oxytocin in 1 L of
RL/5% Dextrose in water)

ONasal spray for milk let- down

46. w ~ …

1. Assess Patient I/O Ratio, Uterine contraction,
BP, pulse & respiration

2. Administer By IV infusion After having crash
cart available in the ward

3. Evaluate patient Length & duration of

contractions and Notify physician of
contractions lasting over one minute or absence

of contractions.

47. Ergot alkaloids are ei
synthetic
Preparations
Ergometrine- 0.25mg/ 0.5mg

ampoules & 0.5-1mg tablets

Methergine - 0.2 mg ampoules & 0.5-1mg tablets
Syntometrine Ergometrine - 0.5 mg+ syntocinon
5.0 units ampoules.

48. it should only. be us e anterior
“shouldé¥ o following delivery of baby.

Q It should not be used in induction of labor or abortion.

OSyntometrine should always be administered IM

Mode of Action
Ergometrine acts directly on the myometrium. It
stimulates uterine contractions & decreases bleeding.

>

49. 1.To stop the atonic.uterin: 9 following delivery,
bortion/ expulsion of hydatidiform mole

Prophylactic

1. As a prophylaxis against excessive hemorrhage , it

may be administered after the delivery of the anterior

shoulder with crowing / following delivery of baby.

ntraindi ion
1. Suspected plural pregnancy
2. Organic cardiac disease
3. Severe Pre-eclampsia & Eclampsia

50. 1. Rise of BP. due n

e2 Prolonged use in puerperium may interfere by
decrease concentration of prolactin & gangrene of toes
due to vasoconstriction.

Dosage and routes of administration ; 4 -
OFor active management of 3“ stage of labour
-0.2mg(iamp) to be given IM.

QFor control of atonic PPH -1amp slowly over 60
seconds, may be repeated after 2hrs.

UFor excessive lochia and subinvolution-1
Tablet(0.125mg)TDS for 3 days.

51. Prostagla om one

® of thé essential fatty acids, archidonic
acid, which is widely distributed
throughout the body. In the female, these
are identified in the menstrual fluid,
endometrium, decidua & amniotic
membrane.

I „co 을 =
2 Pregine! insert] mu al

> ご oc
AA ie

52. Tablet-0-5mg
9. PG E®- Prostin E2 ( Dinoprostone)

Gel-0.5mg E2 in 2.5ml gel-comes in pre loaded syringe.
2. PG F2 alpha- Prostin F2 alpha ( Dinoprostodine)

Inj- 125 and 250mcg

3. PGE1 — Misoprostol
Tablet-100mcg,200mcg,600mcg

Action

Both PGE2 & PGF2 alpha have an oxyto effect on the
pregnant uterus. They also sensitize the myometrium to
oxytocin. PGF2 alpha acts predominantly on the
myometrium, while PGE2 acts mainly on the cervix.

53. ®. For iffaution of labor in IUD of fetus
3. In augmentation/ acceleration of labor

4.To stop bleeding from the open uterine sinuses as in
refractory cases of atonic PPH

5. Cervical ripening

Cóntiaindical
1. Hypersensitivity
2. Uterine fibroids
3. Cervical stenosis
4. PID

54. 2. Dizziness

943. Hypeftensión
4. leg cramps
5. Joint swelling

D rout f ministration
OTablets: containing 0.5 mg prostin E2
vaginal suppository: containing 20 mg PGE2 or 50 mg ピラ エン
alp!

QVaginal pessary: 3mg PGE2

Qinjectable ampoules/vials of prostinE2

O1 mg/ml prostin F2 alpha

O5mg/mi Misoprostol 50mg given 4 hourly by oral, vaginal/ rectal
route for induction of labour

55. a »
개 Assess patient RR, rhythm & depth, vaginal discharge,
itching/ irritation

2. Administer Antiemetic/ antidiarrheal preparations prior
to giving this drug, high in vagina, after warming the
suppository by running warm water over package

3. Evaluate patient for length & duration of contractions,
notify physician of contractions lasting over 1 minute or
absence of contractions, fever & chills

4. Advised patient to remain supine for 10-15 minutes
after vaginal insertion.

56. MAG
© PrepaPatión

Olnj- 1amp=2ml contains 1gm Mgso4.
OTablet-64mg
Action

Decreased acetylcholine in motor nerve terminals,
which is responsible for anticonvulsant properties,
thereby reduces neuromuscular irritability. It also
decreases intracranial edema & helps in diuresis. Its
peripheral vasodilatation effect improves the uterine

blood supply. Has depressant action on the uterine
muscles & CNS

57. 'egn:
2. Used ii

n

1. Heart block

2. Impaired renal function

3. Pregnant women actively progressing labor

Adverse effects

«Maternal

1. Severe CNS depression

2. Evidence of muscular paresis
«Fetal

1.Tachycardia

2. Hypoglycemia

58. >»
1. For control of seizures, 20 mi of 20% solution slowly
in 3-4 mins, to be followed immediately by 10ml of 50%
solution IM & continued 4 hourly till 24 hours
postpartum.

Repeat injections are given only if knee jerks are present,
urine output exceeds 100 ml in 4 hours & respiration are
more than 10/ minute. The therapeutic level of serum
magnesium is 4-7 mEq/L

2. 4gm IV slowly over 10 min, followed by 2 gm/hr and
then 1gm/ hr in drip of 5% dextrose for tocolytic effect

59. ur

w >

1. Assess patients Vital signs 15 min after IV dose, do not
exceed 150 mg/min

2. Monitor magnesium level If using during labour, time of
contractions, determine intensity

3. Urine output should remain 30 ml/hr or more if less
notify physician

4. Examine patient Reflexes-knee jerk, patellar reflex.

5. Administer Only after calcium gluconate is available for
treating magnesium toxicity

60. Inj-1amp-Smg/mi

\ALETHANATE er INJECTION
Action

It is both central and peripheral antimuscarininc agent, which is a
competitive inhibitor of acetylcholine at the muscarinic receptor.

Indication
1. Cervical dilatation in the first stage of labor.
2. Symptomatic relief of Gl tract and ureteric colic.

61. - Pa
2. Myasthe
43. Hypeérterision
4. Ulcerative colitis
5. Closed angle glaucoma
6. CVS disorders
Adverse effects
1. Dryness of mouth
2. Thirst
3. Dilatation of pupil
4. Palpitations
5. Giddiness

62. y necessary.
N i nsi ion:

1. Advise patient to report for any blurred vision,
giddiness ,dry mouth immediately.

2. Advise patient to get up from the bed carefully
and slowly.

63. At birth, the newborn does not have bacteria in
the colon that necessary for synthesizing fat
soluble vitamin k. Therefore newborns have

decreased level of Prothrombin during the first 5
to 8 days of life.

INJ- 그러기 vial=2mg/ml E

al.
az

64. 별. It is USed"to treat or prevent certain bleeding problems.
2. It helps liver to produce blood clotting factors

Contraindications
Hypersensitivity

Adverse effects
1. Pain and edema may occur at injection site.

2. Allergic reaction such as rash and urticarial may
occur.

3. Hyperbilirubinemia

65. Sas

¿na IM within

。 whe
Nursing considerations =
1. Document the giving of the medication | 4 >
newborn to prevent an accidental doubling.

그. Observe for bleeding usually occurs on 2" and
3% day.

3. Observe for jaundice

4. Observe for local inflammation.

66. ~DR

“Here are*the drugs given during puperium
are--
1.Iron

2.Folic acid
3.Calcium De
4.Acetaminophen(paracgarios) 一 =

5.Lactation suppressant (in case of stillbirth,
neonatal death, breast abscess or severe
psychiatric illness.

67. wPrepar#iof
OTablet-80mg,160mg,500mg
Osuppository-80mg,120mg

Qoral solution-16m/ml,80mg/ml

Action
Produce analgesia by inhibiting prostaglandins and other
substances that sensitizes pain re:

dia
1. Mild to moderate pain に

2. Fever

68. "lie Liver diseas
= 2. Hypersensitivity

Adverse effects
. Neutropenia
. Hemolytic anemia

. Hypoglycemia
. Urticaria

AWN =

69. 500
o ~

Nursing considerations

N
DV

1. Advise the patient to not to exceed the

prescribed dose.

2. Advise the patient hat drug is only for short
term use and avoid taking OTC drugs without

prescription.

3. Advise patient to take tablet after meal to

prevent GI symptoms.

70. WTablef0.8fng,2.5mg
Action

It blocks the release of a prolactin from the pituitary
gland.

Indications

Parlodel”
1. Suppression of lactation @romocripts: i
mosyiat) use
2. Pregnancy with prolactinoma SOR E yan
3. Infertility 5 mg 30 Capsuies

Rx only
4.Amenorrhoea

71. 1. Dizziness < rt en getting
sup frorwws lyim position:
2. Confusion
3. Hallucinations
4. Hypertension
5. Seizures
6. Myocardial infarction

D icoutenceadminisiau

A2.5mg tablet orally once in a day.

72. wi. Monitor patient for adverse reaction:

2. Drug may lead to early post partum i]
conception .after menses resumes, ted J
for pregnancy every 4 weeks or as soon
as period is missed

3. Assess orthostatic vital signs before
initiation of the therapy.

4. Instruct the patient to take drug with
meal.

73. ja 연 During Say embryogenesis, the drugs taken by the
mother reach the conceptus through the tubal/ uterine
secretions by diffusion.

2. The harmful effect on the blastocyst is usually death, in
case of survival there is chance of congenital anomalies

3. From 2”-12" week (period of organogenesis) drugs can
cause serious damages

4. Gross congenital malformations & even death of the
fetus may result, depending on route, length of time & dose
of exposure

74. ro

serum al

whaemogilu#ion a.
6. As the albumin binding capacity of the drugs is
decreased more free drug is available for placental an
transfer
7.The metabolism of the drug may be hampered by the
increase in plasma steroids, increased utero-placental
blood flow, increased placental surface area & decreased
thickness of placental membrane are the additional
cause for increased drug transfer
8. Fetotoxic/ teratogenic drugs are prescribed only when
the benefits out weigh the potential risks. Prior
councelling is mandatory & minimum therapeutic dosage
is used for shortest possible duration

75. ct

"Bromides: rash, drowsiness, poor feeding
-lodides: neonatal hypothyroidism
«Chloramphenicol: bone marrow toxicity
-Oral pill: suppression of lactation
Bromocriptine: suppression of lactation
-Ergot: suppression of lactation

-Metronidazol: anorexia, blood dyscrasias,
weakness, neurotoxic disorders

76. „ hepatotoxicity

・ Antithyroid drugs & radioactive iodine:
hypothyroidism & goiter

- Diazepam, opiates, phenobarbitone:
sedation effect with poor sucking reflex.

77. LI
No drug should be administered to a woman durin

pregnancy, labor and birth, unless the woman is fi
informed of the known risks and the relevant area:
uncertainty regarding the effects of the drug onth
physiologic and neurologic development of the woman
or her baby

The drugs that are used daily in obstetric can havea
huge impact on the outcome of both mother and child.
Therefore, obstetric providers need to have a very clear
understanding of the mechanism of action, doses and
side-effects of the most commonly used drugs.