Pharmacology

Question 1

What antibiotics can you not give in pregnancy?

Answer 1

Trimethoprim and nitrofurantoin - teratogenic
Tetracyclines (e.g. doxycycline - affects baby’s teeth)

Consider treating abx with cefalexin or amoxcillin

Question 2

What antibiotics should be prescribed for PPROM?

Answer 2

Erythromycin 250mg QDS - prophylaxis to prevent chorioamnionitis
Suspect infection if high WCC, high CRP, maternal temperatures, fatal tachycardia

Question 3

What antibiotics are given in caesarean sections?

Answer 3

Co-amoxiclav commonly given

Question 4

What steroids are given for fetal lung maturation and how?

Answer 4

Dexamethasone - 4X 6mg doses given as IM injections 12h apart

Beclametasone - 2X 12mg doses given 24h apart

Question 5

What should you consider for the treatment of hypertension in pregnancy?

Answer 5

Labetalol 100mg TDS PO
Or Nifedipine 10mg TDS or QDS
Methyldopa 250mg BD or TDS PO

IF SEVERE labetalol can be given IV or hydralazine or MgSO4

Question 6

What can be given to help prevent pre-eclampsia?

Answer 6

Low dose aspirin (75mg)

Question 7

What else is MgSO4 useful for?

Answer 7

NEUROPROTECTION - should be given to all women in pre-term labour BEFORE 30 weeks

Question 8

What anti-emetics should be considered in hyperemesis?

Answer 8

Cyclizine 50mg TDS PO
Prochlorperazine 10mg TDS
Promethiazine 25mg TDS
Chlorpromazine 10-25mg

THEN

Metaclopramide (5-10mg) or ondansetron

THEN

Corticosteroids e.g. hydrocortisone (consultant decision)

Question 9

What laxatives should be considered in constipation in pregnancy?

Answer 9

BULK-FORMING (e.g. methycellulose)

LACTULOSE is also commonly given

Question 10

What pharmacological treatment could you consider for obstetric cholestasis?

Answer 10

Ursodeoxycholic acid - reduces cholesterol absorption for the intestines helping with the dissolving of cholesterol
8-12mg OD before bed

Question 11

What pharmacological treatments can be considered for PPH?

Answer 11

SYNTOMETRINE - (syntocinon and ergometrine for contraction of uterus)
CARBOPROST (PG analogue) - helps to contract down uterus 250mcg doses no less than 15mins apart no more than 2mg max

If these things fail consider surgical management - Intra-Uterine balloon tamponade, B-lynch sutures, uterine or iliac artery ligation, hysterectomy

Question 12

When can a termination of pregnancy be managed MEDICALLY?

Answer 12

TOP can only be managed medically if the woman is less than 9 weeks

Question 13

What is the first stage of treatment for a medical TOP?

Answer 13

Mifepristone - competitive progesterone receptor antagonist
- this terminates the pregnancy but then the woman requires some assistance to pass the pregnancy and this is when the next stage is given

Question 14

What is the second stage of management for a TOP?

Answer 14

Misopristol. This is a prostaglandin analogue that helps the woman’s body to pass the terminated pregnancy

Question 15

When can a medical management of an ectopic pregnancy can be considered?

Answer 15

• if pregnancy has not ruptured
• If woman has no symptoms or pain
• If woman BHCG levels are <1500
• If there is no fetal heart beat
• If intra-uterine pregnancy has been effectively ruled out

**if a woman does not fulfil these criteria should consider surgical management of the ectopic either with salpingectomy or salpingostomy

Question 16

What can be used to medically manage a top?

Answer 16

METHOTREXATE

Question 17

What treatment options are there for heavy menstrual bleeding?

Answer 17

Tranexamic acid and mefenamic acid

Question 18

How does tranexamic work? How is it taken?

Answer 18

TXA - is an anti-fibrinolytic
It has a very short half life and so should be taken as 1g PO TDS-QDS
***Still able to take it if you are trying to conceive

Question 19

How does mefenamic acid work and how is it taken?

Answer 19

Mefenamic acid is an NSAID and is one of the most commonly prescribed treatments for HMB
NSAIDS inhibit the cyclo-oxygenases meaning the production of both prostaglandins and thromboxanes are inhibited
500mg PO TDS

Question 20

What are the high risk factors for VTE in pregnancy and what should be offered?

Answer 20

Previous history of VTE

Offer 4500U tinzaparin

Question 21

What are some intermediate risk factors for VTE in pregnancy and what should be offered?

Answer 21

Hospital admission
Single prev VTE related to major surgery
High risk thrombophilia
High risk co-morbidities (SLE, heart failure, cancer, T1DM, IBD, arthropathy, sickle cell disease, IVDU)
Surgical procedure

CONSIDER Tinzaparin 4500

Question 22

What are some low risk factors for VTE in pregnancy and what would make you consider prophylaxis?

Answer 22

BMI >30 
Age >35
Parity of 3 or more 
Smoker 
Gross varicose veins 
Immobility 
FH of unprovoked or oestrogen provoked VTE
Current pre-eclampsia 
Low risk thrombophilia 
Multiple pregnancy 
IVF/ART 

***if 4 OR MORE of these factors exist consider 4500 tinzaparin

Question 23

If you decide a woman DOES NOT need VTE prophylaxis in pregnancy what advice can you give?

Answer 23

Stay mobile and hydrated

Question 24

What are some high risk factors for VTE in the post-natal period? What prophylaxis should be given?

Answer 24

Previous VTE 
LMWH in pregnancy 
High risk thrombophilia
Low risk thrombophilia + FH 
Give LWMH 4500 for at least 6 weeks

Question 25

What are some intermediate risk factor for VTE in the post natal period and what prophylaxis should you consider?

Answer 25

C-section
BMI >40
Re-admission or prolonged admission (>3 days) in puerperium
Surgery in puerperium apart from immediate perineal repair
Medical comorbidities (cancer, SLE, nephrotic syndrome, T1DM, sickle cell disease, IBD and arthropathy)

Give AT LEAST 10 days prophylactic LMWH

Question 26

What are some low risk factors for VTE in the post-natal period and when should you consider prophylaxis?

Answer 26

Age >35 
Obesity. BMI >30
Parity of 3 or more 
Smoker Elective c-section 
FHx VTE 
Low risk thrombophilia 
Gross varicose veins 
Systemic infection 
Immobility 
Current pre-eclampsia 
Multiple pregnancy 
Pre-term delivery in this pregnancy
Still birth in this pregnancy 
Mid cavity rotation or operative delivery 
Prolonged labour >24h
PPH >1L blood transfusion 

IF 2 OR MORE RFx - 7-10 days LMWH
If less than 2 advise mobility and hydration