Pharmacology Flashcards
What antibiotics can you not give in pregnancy? (4)
Trimethoprim-because anti folate (do not use in1st trimester)
Nitrofurantoin-causes neonatal heamolysis (do not use in 3rd trimester)
Tetracyclines (e.g. doxycycline - affects baby’s teeth)
Co-amoxiclav can cause NEC in preterm baby
What antibiotics should be prescribed for PPROM?
symptoms that would make you suspicious?
Erythromycin 250mg QDS - prophylaxis to prevent chorioamnionitis (can be devastating)
Suspect infection if high WCC, high CRP, maternal temperatures, fatal tachycardia
What antibiotics are given in caesarean sections?
Co-amoxiclav commonly given
What steroids are given for fetal lung maturation and how?
Dexamethasone - 4X 6mg doses given as IM injections 12h apart
Beclametasone - 2X 12mg doses given 24h apart
What should you consider for the treatment of hypertension in pregnancy?
1st line: Labetalol 200mg (beta blocker)
2nd line: Or Nifedipine 10mg (if asthmatic)
3rd line: Methyldopa (must be stopped post partum-risk of depression)
IF SEVERE/refractive: IV labetalol or IV or hydralazine
What can be given to help prevent pre-eclampsia?
Low dose aspirin (75mg) from 12 weeks to birth
What else is MgSO4 useful for?
NEUROPROTECTION - should be given to all women in pre-term labour BEFORE 30 weeks
What anti-emetics should be considered in hyperemesis?
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)
What laxatives should be considered in constipation in pregnancy?
BULK-FORMING (e.g. methycellulose)
LACTULOSE is also commonly given
What pharmacological treatment could you consider for obstetric cholestasis?
Ursodeoxycholic acid - reduces cholesterol absorption for the intestines helping with the dissolving of cholesterol
8-12mg OD before bed
What pharmacological treatments can be considered for PPH?
(probs caused by atony)
1st line: mechanically squeeze
2nd line:
- 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
3rd line
- If these things fail consider SURGICAL management
- Intra-Uterine balloon tamponade, B-lynch sutures, uterine or iliac artery ligation, hysterectomy
When can a termination of pregnancy be managed MEDICALLY?
TOP can only be managed medically if the woman is less than 9 weeks
What is the first stage of treatment for a medical TOP?
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
What is the second stage of management for a TOP?
Misopristol. This is a prostaglandin analogue that helps the woman’s body to pass the terminated pregnancy
When can a medical management of an ectopic pregnancy can be considered?
- 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
What can be used to medically manage an ectopic pregnancy
METHOTREXATE
What treatment options are there for heavy menstrual bleeding?
Tranexamic acid and mefenamic acid
How does tranexamic work? How is it taken?
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
How does mefenamic acid work and how is it taken?
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
What are the high risk factors for VTE in pregnancy and what should be offered?
Previous history of VTE
Offer 4500U tinzaparin (LMWH)
What are some intermediate risk factors for VTE in pregnancy and what should be offered?
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 (LMWH) 4500
What are some low risk factors for VTE in pregnancy and what would make you consider prophylaxis?
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 (LMWH)
If you decide a woman DOES NOT need VTE prophylaxis in pregnancy what advice can you give?
Stay mobile and hydrated
What are some high risk factors for VTE in the post-natal period? What prophylaxis should be given?
Previous VTE
High risk thrombophilia
Low risk thrombophilia + FH
Give LWMH (tinzaparin) 4500 for at least 6 weeks
What are some intermediate risk factor for VTE in the post natal period and what prophylaxis should you consider?
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 (tinzaparin)
What are some low risk factors for VTE in the post-natal period and when should you consider prophylaxis?
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
Can you give warfarin in pregnancy? Why?
- Can’t give warfarin in pregnancy
- Fetal warfarin syndroms (hypoplasia of nose and extremities/developmental delay)
- except patients with mechanical valves (12-36 weeks)
What drugs should you use in UTI in pregnancy?
1st line nitrofurantoin (avoid at term or if eGFR <45 ml/minute)
2nd line cefalexin or amoxicillin if culture is back
**avoid co-amoxiclav (causes NEC in baby)
What would you give for RTI?
Penicillins and macrolides are safe
What should you give for chorioamnionitis?
Cefuroxime and metronidazole
What is endometritis?
Common organisims?
- Infection within the uterus after birth
- More common after CS
- Most commonly group A streptococcus (strep pyogenes)
What are signs of endometritis?
Endometritis
- Offensive lochia
- Fever
- Tachycardia
- Suprapubic tenderness/uterine enlargement
Investigations for endometritis
FBC, CRP, blood cultures , high vaginal swab (HSV)
What should you give for endometritis? (infection of uturus after birth)
Co amoxiclav (if penicillin allergic give clindamycin and metronidazole)
What drugs would you give in epilepsy?
What should all epileptic pregnancy women also take?
What should you avoid?
1st line
- Lamotrogine
- Leviter-ac-etam
ALSO take high dose 5mg folic acid
AVOID valporate (neural tube defects)
What contraceptions can be used in the post partum period?
What are contraindicated?
-progesterones are safe (coils and implants often put in on ward)
Combined hormonal contraceptions (oestrogen) are contraindicated (thrombus risk)
