Prescribing in Pregnancy: A Practical ED Guide

Pregnant patients frequently present to the Emergency Department (ED) with symptoms like pain, nausea, or infection. While prescribing during pregnancy can feel daunting due to concerns about foetal harm, hesitation can unfortunately lead to under-treatment, unnecessary admissions, or unsafe self-medication.

The good news? Safe, effective treatments do exist.

This practical guide equips ED clinicians with evidence-based recommendations for prescribing confidently not cautiously using trusted sources such as the Royal College of Obstetricians and Gynaecologists (RCOG), the UK Teratology Information Service (UKTIS), and the British National Formulary (BNF).

Disclaimer: This blog is for educational purposes. Always follow local prescribing guidance and discuss individual risks with patients.

1. Pain Relief

Pain is one of the most common reasons pregnant patients present to the ED often due to back pain, headaches, or abdominal discomfort. Providing adequate analgesia during pregnancy¹ is essential for maternal wellbeing and is safe when chosen appropriately.

2. Antiemetics

Nausea and vomiting are very common in pregnancy. Severe cases hyperemesis⁴ may lead to dehydration or electrolyte disturbance, needing ED management.

3. Allergy Management

Urticaria, allergic rhinitis, and insect bites are common. Non-sedating antihistamines are preferred, but sedating ones can be helpful if sleep is affected.

4. Reflux: Proton Pump Inhibitors (PPIs)

Heartburn and acid reflux are frequent complaints, especially later in pregnancy. Antacids can be used, but PPIs are often needed for persistent symptoms.⁵

5. Corticosteroids

Corticosteroids are used in pregnancy ⁶ for asthma exacerbations, autoimmune disease flares, or foetal lung maturation (in preterm labour).

Steroid	Use Case
Prednisolone	Preferred for maternal asthma or autoimmune.
Dexamethasone/Betamethasone	Used for foetal lung maturation (2434 weeks).

Short-term courses of corticosteroids are generally considered safe. However, high doses or long-term use should be avoided whenever possible.

6. Constipation & Laxatives

Constipation in pregnancy⁷ is common due to hormones and reduced gut motility. Hydration and dietary fibre are first line; laxatives can be added if needed.

Quick Reference: Safe First-Line Options by Symptom

7. Antibiotics in Pregnancy Whats Safe in the ED?

Prompt treatment of infections (e.g., UTI, chest infection, cellulitis) is essential. Delayed antibiotics can be more harmful than the drugs themselves.

Drug/Class	Pregnancy Use	Breastfeeding	Notes
Penicillin	Safe throughout	Safe	Always check allergies.
Cephalosporins	Safe throughout	Safe	Low cross-reactivity.
Co-amoxiclav	Safe when needed	Safe	Useful for polymicrobial infections.
Erythromycin	Safe	Safe	May cause GI upset.
Nitrofurantoin	Avoid at term	G6PD caution	Safe mid-pregnancy.
Acyclovir	Likely safe	Monitor infant	High milk transfer but generally tolerated.
Trimethoprim	Avoid in first trimester	Yes	Folate antagonist.
Metronidazole	Short courses only	Avoid high dose	Avoid 2g stat; breastfeeding caution.
Clarithromycin/Azithromycin	Use only if needed	Limited data	Reserve for resistant cases.
Tetracyclines	Avoid	Avoid	Tooth and bone risk.
Gentamicin	Avoid	Use caution	Ototoxicity risk.
Quinolones	Avoid	Use caution	Cartilage toxicity.
Fluconazole	Avoid	Use caution	Dose-related teratogenicity.

Final Take-Home Points

• Many safe options exist dont be afraid to treat
• Always check breastfeeding safety
• Document clinical reasoning and safety discussion
• Reassure patients: informed prescribing avoids both harm and undertreatment.

References and Further Reading

1. Li L, Chieng D, Bhuva S, Cox C, Gordon A. Pain relief and analgesia during pregnancy: what’s safe? BJOG. 2021;128(4):621630.
2. UK Teratology Information Service. Use of non-steroidal anti-inflammatory drugs (NSAIDs) in pregnancy [Internet]. 2022 [cited 2025 Jun 1].
3. UK Teratology Information Service. Use of codeine or dihydrocodeine in pregnancy [Internet]. 2022 [cited 2025 Jun 1].
4. Dean CE, Henry A, et al. Management of nausea and vomiting in pregnancy. BJOG. 2021;128(10):15941602.
5. UK Teratology Information Service. Use of proton pump inhibitors (PPIs) in pregnancy [Internet]. 2022 [cited 2025 Jun 1].
6. UK Teratology Information Service. Use of systemic corticosteroids in pregnancy [Internet]. 2022 [cited 2025 Jun 1].
7. UK Teratology Information Service. Treatment of constipation in pregnancy [Internet]. 2022 [cited 2025 Jun 1].