A1. Drug use in pregnancy and minor ailments in pregnancy

Question 1

Describe the trimesters

Answer 1

1st trimester: 1-12 weeks
2nd trimester: 13-27 weeks
3rd trimester: 28-40 weeks

Question 2

what are the different stages of development?

Answer 2

-pre embryonic: 0-17 days, implantation of fertilised ovum
-embryonic: 18-56 days, major organ systems development
-foetal: 8-38 weeks, maturation, development and growth

Question 3

what are the different issues in pregnancy?

Answer 3

-Women may have taken medicines unaware that they are pregnant
-Want to become pregnant but require essential treatment for chronic medical condition
-Require treatment for a medical condition after they know they are
pregnant e.g. N&V, hypertension

Question 4

what changes in absorption occur?

Answer 4

-reduced gut mobility
-increased lung function
-increased skin blood circulation

Question 5

Describe changes in distribution

Answer 5

-reduced plasma proteins
-increased plasma volume
-increased body water
-increased fat disposition

Question 6

Describe changes in metabolism

Answer 6

-Enzyme induction typically increased
-Affects on drugs difficult to predict
-Methadone/phenytoin may need higher maintenance doses
-Theophylline may need lower doses
-Monitor drugs with narrow therapeutic range

Question 7

Describe changes in elimination

Answer 7

-Increased glomerular filtration
-Increased penicillin & digoxin elimination

Question 8

what is a teratogen?

Answer 8

An agent that directly or indirectly causes structural or functional
abnormalities in the foetus, or child after birth, which may not
become apparent until later life

Question 9

what are the principles of a teratogen?

Answer 9

-Timing of exposure
-Differences in susceptibility
-Dose-response relationships

Question 10

Describe the effect of teratogen on the timing of exposure

Answer 10

-pre-embryonic phase: ‘all or nothing’ principle
-embryonic phase: greatest risk of major birth defects
-foetal phase: Less susceptible to toxic effects but some structural/ functional abnormalities and growth retardation

Question 11

Describe the effect of teratogen on the differences in susceptibility

Answer 11

-Drugs harmless to mother can cause severe damage to embryo or foetus
-no placental barrier to most drugs so foetus will be exposed

Question 12

Describe the effect of teratogen on dose-response relationships

Answer 12

-Teratogenic effects are
dose-dependent
-Dose-response curve is steep
-Cumulative exposure of drug to foetus is important

Question 13

Describe placental drug transfer

Answer 13

-Most drugs will cross the placenta
-Except high molecular weight drugs e.g. insulin, heparin
-Lipid, soluble, unionised drugs cross the placenta more easily than polar, ionised, hydrophilic drugs
-Pharmacological effects
* Direct e.g. warfarin
* Indirect e.g. antihypertensive

Question 14

describe drugs for foetal disorders

Answer 14

Drugs may be administered to a pregnant woman to treat foetal disorders

Question 15

what drugs taken by men can cause adverse effects on fetus?

Answer 15

-Finasteride
-Griseofulvin

Question 16

Describe the effects of maternal drug use on the neonate

Answer 16

Issues relating from maternal drug use during the latter stages of pregnancy:
-Allergic drug reactions (sensitised in uterus)
-Reduced capacity for drug elimination (accumulation)
-Withdrawal effects: Morphine oral solution used to wean babies off methadone

Question 17

key principles for drug use in pregnancy?

Answer 17

-consider non- drug treatment
-only when necessary
-consider period of gestation
-avoid new drugs
-avoid polypharmacy
-lowest effective dose for minimum time
-don’t use known teratogens
-know what questions to ask
-know where to look

Question 18

pre-conception advice?

Answer 18

-All women should be offered advice to minimise risk of congenital abnormalities
-Avoidance of all drugs, alcohol, herbal remedies, smoking and
vitamin A products
-Folic acid supplementation
-Seek specialist advice for chronic illnesses requiring drug treatment

Question 19

Questions to ask a pregnant woman as a pharmacist?

Answer 19

-Drug? Indication?Dose?Frequency?Route? Duration?
-Stage of pregnancy?
-Previous pregnancy?
-Family history?
-Investigations?
-Retrospective exposure?

Question 20

Sources of advice for pharmacists?

Answer 20

-BNF (see individual monographs)
-SPC
-Micromedex
-Martindale
-Specialist Books
-Medicines Information Centre
-UK Teratology Information Service (UKTIS) –Newcastle
-Bumps

Question 21

Describe OTC sale of medicines for pregnant women

Answer 21

-Limited by manufacturers
licensing restrictions
-Not necessarily due to
lack of safety
-Refer to patient information leaflet (PIL)
-When no suitable OTC product can be recommended seek
alternative strategies

Question 22

Lifestyle changes for gastro-oesophageal Reflux Disease?

Answer 22

-Adopt healthy eating habits, eat smaller meals more frequently
-Avoid known irritants: chocolate, fatty or spicy foods, fruit juices, coffee and alcohol
-Do not eat within 3 hours of going to bed
-Raising the head of their bed
-Avoid medicines if appropriate (e.g. sedatives, calcium-channel antagonists, antidepressants, non-steroidal anti-inflammatory drugs)
-Stop smoking (if possible)

Question 23

Treatment options for gastro-oesophageal Reflux Disease?

Answer 23

-Antacids and alginates are recommended for mild
symptoms not controlled by lifestyle changes
-E.g. Gaviscon advance®
-If not adequately controlled with OTC or lifestyle advice refer to GP who may prescribe omeprazole

Question 24

Lifestyle changes with constipation?

Answer 24

-Increase fibre intake
-Increase fluid intake
-Examples of food rich in fibre include:
-wheat, oat or bran cereals
-wholegrain pasta, bread and rice
-beans and lentils
-fruit and vegetables
-Increased physical activity

Question 25

How to treat constipation (medication)?

Answer 25

Licenced OTC preparations: -1st choice – Fybogel Hi-Fibre ® -Alternatives - Lactulose (both laxatives)

Question 26

How to treat haemorrhoids/piles?

Answer 26

-Topical haemorrhoidal cream or ointment containing mild astringents or antiseptics -E.g. Anusol® -Preparations containing anaesthetics or corticosteroids should only be used in pregnancy when prescribed by a doctor -Diet and Lifestyle -Sufficient fibre and fluid to promote soft stools

Question 27

Pregnant women with thrush?

Answer 27

All pregnant women with suspected thrush should be referred to their GP

Question 28

Treatment options for thrush?

Answer 28

-Doctor may prescribe a topical antifungal -Include creams or pessaries for inserting into the vagina and external creams for symptoms around the vulva -Example: clotrimazole -Advise patient to use fingers to insert pessaries as applicators may cause damage to the cervix -For unresponsive symptoms they may prescribe oral fluconazole

Question 29

Lifestyle/diet changes for nausea and vomiting?

Answer 29

-drink plenty -rest and sleep -avoid triggers -Eat small, frequent protein-rich meals, low in carbohydrates and fat -Avoid drinking cold, tart, or sweet beverages -Eat plain biscuits about 20 minutes before getting up -Acupressure to the wrist -ginger

Question 30

what are red flag symptoms?

Answer 30

-Very dark urine, or no urination for ≥8 hours -Abdominal pain or fever -Severe weakness or feeling faint -Vomiting blood -Repeated, unstoppable vomiting -Inability to keep down food or fluids for 24 hours

Question 31

How to treat pain?

Answer 31

-Restricted to paracetamol -Only take if needed -Exercise/Physiotherapy -Transcutaneous electrical nerve stimulation (TENS) in the early stages of labour