Prescribing in pregnancy



NICE guidelines

  • Discuss the benefits and harms of treatment
  • For advice when dealing with antidpressants for pregnant women contact
  • NO ANTIDEPRESSANT HAS BEEN PROVEN SAFE IN PREGNANCY but the following are safer than others:


  • Generally considered an option during pregnancy:
  • Citalopram
  • Sertraline
  • Potential complications include maternal weight changes and premature birth
  • Most studies show that SSRIs are not associated with birth defects.
  • Avoid paroxetine due to increased risk of a fetal heart defect


  • duloxetine
  • venlafaxine 

Tricyclic antidepressants. 

  • nortriptyline
  • Not first or second line but might be an option for women who haven't responded to other medications
  • clomipramine might be associated with fetal birth defects, including heart defects 

Last trimester

  • antidepressants during the last trimester may result in baby experiencing temporary discontinuation symptoms
    • jitters, irritability, poor feeding and respiratory distress
    • for up to a month after birth
  • No evidence that discontinuing or tapering dosages near the end of pregnancy reduces the risk of these symptoms
  • This might even increase your risk of a relapse postpartum
Link to share with patients



  • Always ask patient to come in for MSU and send for culture
  • Start empirical antibiotics in all pregnant patients with significant positive culture, even if asymptomatic
  • First line
    • nitrofurantoin (avoid at term) 100mg MR bd 7 days
  • Second line
    • trimethoprim 200mg BD for 7 days
    • give folic acid 5mg OD if 1st trimester
    • avoid if folate low or on folate agonist (eg methotrexate)
  • Third line
    • cefalexin 500mg BD for 7 days 

do we look at what the MSU is sensitive to?

Vitamin D

  • Rickets is re-emerging in children from ethnic minorities 
  • During pregnancy, maternal vitamin D deficiency can lead to deficiency in the infant does midwife measure vit d at initial visit?
  • There is a lack of safety or outcome data of vitamin D supplementation in the first trimester
  • Majority of skeletal growth and development occurs n the 2nd or 3rd trimester

Prevention in women suspected to be of high risk of deficiency

  • women with darker skin tones
  • reduced exposure to sunlight
  • those who are socially excluded
  • obese 
  • First trimester
    • DOH suggests 400units (10mcg) 
  • Second & third trimester
    • Minimum 1000units/day 


  • <25-30nmol/L
    • 2000-4000units/day for up to 11 weeks 
  • < 15nmol/L in third trimester then slightly faster or even rapid correction may be required by specialist

Iron deficiency 

Ferrous fumarate 305mg bd ususally until delivery 

Floradix liquid - available OTC and safe in pregnancy 


  • Advice to pregnant woman
    • Avoid any foods or smells that trigger symptoms (for example spicy or fatty foods)
    • Eat plain biscuits or crackers in the morning before getting up
    • Eat bland, small, frequent meals low in carbohydrate and fat but high in protei
    • Cold meals may be more easily tolerated if nausea is smell-related
    • Drinking little and often rather than large amounts, as this may help to prevent vomiting
    • Ginger
    • Acupressure
    • Avoid iron-containing preparations if they make symptoms worse

Red flags

  • Seek urgent medical advice if they experience:Very dark urine, or no urination for more than 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
    • Severe headache
    • Visual problems
    • Severe pain below the ribs
    • Sudden swelling of the face, hands, or feet (symptoms of pre-eclampsia) 


  • Firstline 
    • Cyclizine 50 mg up to 3 times a day
    • Promethazine 20–25 mg od 
    • Prochlorperazine 20 mg on acute attack then 10 mg after 2 hours then 10mg tds as prevention
    • domperidone - Use only if potential benefit outweighs risk - some guidelines contraindicate due to teratogenicity observed in reproductive toxicity studies
  • Secondline
    • Metoclopramide 10mg tds for a maxiumum of 5 days
    • Ondansetron (Max 5 days as per NICE) 
      • NICE Guidelines advises exposure to ondansetron during the first trimester of pregnancy is associated with a small increased risk of the baby having a cleft lip and/or cleft palate
      • Manufacturer advises avoid in first trimester due to the small increased risk of congenital abnormalities such as orofacial clefts
      • Prescribers should refer to clinical guidance if treatment with ondansetron is considered for severe nausea and vomiting in pregnancy and, make an informed decision
      • The Medicines and Healthcare products Regulatory Agency (MHRA) advises that if a licensed product is not available or not suitable or not sufficient alone to control severe nausea and vomiting in pregnancy, and there is a special clinical need to use ondansetron, then the decision to prescribe ondansetron decision should be made in consultation with the patient after she has been fully informed of the potential benefits and risks of the different treatment options
  • Alternative
    • Xonvea: doxylamine succinate 10 mg/ pyridoxine hydrochloride 10 mg
    • 20/20 mg once daily for 2 days, to be taken at bedtime; increased if necessary to 10/10 mg, to be taken in the morning and 20/20 mg, to be taken at bedtime; increased if necessary to 10/10 mg, to be taken in the morning, 10/10 mg, to be taken mid-afternoon and 20/20 mg, to be taken at bedtime; maximum 40/40 mg per day.
    • is a delayed-release tablet containing doxylamine succinate 10 mg (an antihistamine) and pyridoxine hydrochloride 10 mg (vitamin B6).
    • licensed for nausea and vomiting of pregnancy in women (aged 18 years or older) who do not respond to conservative management. 

Review after 24 hours then after 7 days 

  • If the response to the treatment is good continue treatment
  • If the response is inadequate, the woman is not dehydrated, and there is no ketonuria switch to another anti-emetic from a different class
  • Seek specialist advice if the response to a second anti-emetic is poor 

Stop antiemetic

  • Stop after around 12-16 weeks, by which time symptoms have usually improved
  • Third trimester: Avoid antihistamines

Patient Information


Chlorpheniramine maleate can be used with caution in these circumstances.

pregnant patient should be informed that no antihistamine drug can be considered absolutely safe but that the small risk has to be balanced against the benefits of keeping the mother healthy in the interest of the foetus. Prescribed drugs must be selected cautiously after the patient has been informed of the potential adverse effects

  • data sheets for cetirizine, desloratadine, hydroxyzine and loratadine all advise avoidance in pregnancy8mn 
  • high doses of hydroxyzine and loratadine have caused embryotoxicity in animal studies
  • chlorphenamine and loratadine appear to be associated with no evidence of an icnreased incidence of congenital abnormality if used during pregnancy
  • chlorpheniramine - there is one case report of neonatal respiratory depression following use in the third trimester and although a causal relationship was not established there is a data sheet warning that use of chlorphenamine in the third trimester may result in reactions in neonates
  • there is no evidence of teratogenicity
  • using the lowest dose possible chlorphenamine or loratadine are the antihistamines of choice in pregnancy. There is less clinical experience with cetirizine in pregnancy and therefore it should only be considered as a second-line agent
  • Use in the latter part of the third trimester may cause adverse effects in neonates such as irritability, paradoxical excitability, and tremor
  • embryotoxicity in animal studies with high doses of hydroxyzine and loratadine
  • best practice to avoid taking drugs in pregnancy, as present knowledge is incomplete
  • Urticaria
    • often improves in pregnancy, reducing the need for antihistamine treatmen
    • in some rare cases symptoms of urticaria worsen
  • Hayfever advice
    • Steam inhalation
    • Vaseline
    • Sterimar nasal spray
    • Sunglasses
    • Cucumber eye mask
    • Windows closed
    • avoid drying clothes outside
    • avoid cutting grass
    • Take a shower and change your clothes after being outdoors to remove the pollen on your body
  • Breast feeding:
    • significant amount of some antihistamines present in milk
    • although not known to be harmful, manufacturers of alimemazine, cetirizine, cinnarizine, cyproheptadine, desloratadine, dimenhydrinate, fexofenadine, hydroxyzine, loratadine, ketofen and mizolastine advise avoid
    • adverse effects in infant reported with clemastine
    • antihistamines should only be used during lactation when the clinical imperative outweighs the potential harm to the child and the lowest possible dose used for the shortest possible duration.
    • Chlorphenamine has been reported to cause drowsiness and poor feeding
    • both loratadine and cetirizine appear much safer with only low levels found in breast milk and therefore either of these drugs can be considered if required 

Gestational Hypertension

  • Aim for BP 150/100

Mild Hypertension: 140/90-149/99

  • Labetolol
    • Initially 100 mg twice daily, dose to be increased at intervals of 14 days; usual dose 200 mg twice daily, increased if necessary up to 800 mg daily in 2 divided doses, to be taken with food, higher doses to be given in 3–4 divided doses; maximum 2.4 g per day
  • Nifedipine
    • If labetalol is contraindicated, fails to control the blood pressure after one or two stat doses of Labetalol
    • 10mg oral tablet (not a slow-release tablet)
  • Measure BP twice weekly
  • Monitor urinary protein: creatinine ratio at each visit
  • U&E, FBC, LFT at each visit

Severe Hypertension: 160/110

  • Admit to hospital

Post natal

  • Measure BP every 1–2 days for up to 2 weeks after transfer to community care, until antihypertensive treatment stopped and no hypertension
    • if BP > 150/100 on two occasions 30 minutes apart - Prescribe oral antihypertensives
    • BP < 130/80 - reduce treatment
    • BP <120/70 - stop treatment
  • If breast feeding - Beta blockers (eg. Atenolol, labetalol), alpha-adrenergic blockers (eg. doxazosin) and calcium antagonists (eg. nifedipine, amlodopine)
  • Diuretic treatment should be avoided in breastfeeding women
  • Methyldopa should not be prescribed postnatally
  • After pre-eclampsia, blood pressure can take up to 3 months to return to normal. During this time, blood pressure should not be allowed to exceed 160/110 mmHg
  • All patients with severe pre-eclampsia who remain hypertensive or proteinuria >1+ should be offered a hospital appointment 6-8 weeks post-delivery


Pregnant women with increased risk of pre-eclampsia should be prescribed 75–150 mg of aspirin to take daily from 12 weeks until birth - if TWO or more of the following:

  • over 40 years
  • first time pregnancy
  • more than 10 years since last pregnancy
  • BMI >35
  • FH of pre-ecalmpsia
  • expecting multiple babies



  • strongly recommend referral to a genito-urinary medicine (GUM) clinic for management 
  • If the person declines, or is unable to attend a GUM clinic, manage in primary care


  • Azithromycin, 1 g orally for one day, then 500mg orally once daily for two days, or
  • Erythromycin 500 mg four times daily for seven days, or
  • Erythromycin 500 mg twice daily for 14 days, or
  • Amoxicillin 500 mg three times a day for seven days


The following must be covered:

  • Advise that sexual intercourse (including oral sex) should be avoided until the person and their partner(s) have completed treatment (or waited 7 days after treatment with azithromycin)
  • Refer all people with confirmed chlamydia infection to a GUM clinic for partner notification, for screening of other STIs.
  • If the person is unwilling or unable to attend a GUM clinic, advise them that (with their consent) their details can be provided to the GUM clinic solely for the purposes of partner notification
  • 5. Ensure that the person's current partner is treated for chlamydia irrespective of their screening result
  • 6. Urgently refer the person to GUM if there is no response to first-line treatment

Patient Information

Chlamydia Patient Information Leaflet

 Chlamydia Management form from folder


Planning a pregnancy

  • Check thyroid function before conception
    • If TFTs are not within the euthyroid range, advise delaying conception, until stabilised on levothyroxine treatment
  • Check that the woman understands that her dose of levothyroxine must be adjusted as early as possible in pregnancy to reduce the chance of obstetric and neonatal dammage


  • Patients with established hypothyroidism should have levothyroxine dose increased by 25 micrograms as soon as a positive pregnancy test is found
  • Check thyroid function after 2 weeks 
  •  Aim for
    • T4 16-21 pmol/L
    • TSH <2 mU/L
  • Refer to an endocrinology specialist all women with overt or subclinical hypothyroidism is this correct?
  • Check thyroid function every trimester
  • Cut back T4 dose to pre-pregnancy dose 2-6 weeks post-partum 


  • Refer all women with hyperthyroidism in pregnancy to endocrinologist is this correct?
  • Measure TRAbs in all patients with Graves disease
  • Patients with detectable TRAbs require special management, irrespective of their thyroid function test profile.
  • The aim is for good control of hyperthyroidism on the minimum dose of carbimazole / propylthiouracil possible


Switch Carbimazole to Propylthiouracil (PTU) as soon as possible. 

Other long term medications during pregnancy

  • Inhaled drugs for asthma can be taken as normal during pregnancy
  • Metformin - Can be used in pregnancy for both pre-existing and gestational diabetes. Women with gestational diabetes should discontinue treatment after giving birth
  • Beta-blockers may cause intra-uterine growth restriction, neonatal hypoglycaemia, and bradycardia; the risk is greater in severe hypertension
  • High doses teratogenic in animals but therapeutic doses unlikely to be harmful

Erythromycin Trimethoprim venlafaxine Sertraline Citalopram Duloxetine nortriptyline azithromycin Amoxicillin Propylthiouracil levothyroxine Carbimazole Cyclizine Promethazine Prochlorperazine Metoclopramide Ondansetron Labetolol

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