Pharmacy

Medicines in pregnancy

Many women need to take medicines during pregnancy for either new or ongoing conditions that require treatment. Every pregnancy begins with a 3 to 5 percent chance of developing a birth defect, which is called the ‘background risk’. Medicine exposure accounts for only a small proportion of these birth defects.

Pregnancy can also impact the way that the body processes medicines, which can lead to changes in the amount of medicine you need. It is important to consider the risks and benefits of treating a condition with medicine versus the potential effects of that medicine on the pregnancy.

It is recommended that medicines are used at the lowest effective dose for the shortest possible duration.

The impact of medicine on the fetus can vary throughout the pregnancy, depending on the period it is taken. In very early pregnancy, a harmful exposure is most likely to cause an ‘all or nothing’ response - meaning that it may either cause a miscarriage or not have a significant effect on the pregnancy. During the first trimester, harmful exposures are most likely to cause birth defects because this is when major structural formation occurs. In the second and third trimester, harmful exposures are more likely to cause growth problems, preterm birth and newborn withdrawal symptoms.

 

Important information

It is important that all decisions relating to medicine use in pregnancy are made with your healthcare providers. Before starting, continuing, changing or stopping a medicine during pregnancy, it should be discussed with a doctor, pharmacist and / or midwife.

 

Commonly used medication

Hay fever and allergies

Hay fever symptoms include a runny or blocked nose, sneezing, itching of the eyes or nose and watery, irritated eyes. Avoiding or limiting exposure to substances that cause hay fever, such as pollens, house dust mites and animal dander, can help reduce symptoms.

Simple measures such as saline nasal sprays can assist in removing allergens from the nasal passages.

Oral and nasal antihistamines
Antihistamines reduce the symptoms of hay fever but don’t always help nasal congestion. There is more safety information about the older oral sedating antihistamines, such as promethazine and dexchlorpheniramine, and they may be used at recommended doses at any stage in pregnancy. Less sedating oral antihistamines, such as loratadine, are also considered safe to use in pregnancy at recommended doses.

Antihistamine nasal sprays and eye drops containing azelastine, levocabastine and ketotifen (eye preparation only) can be used when needed to relieve symptoms of hay fever and are safe to use in pregnancy. They generally start to work quickly after use (usually within 15 minutes). When using eye drops, apply pressure against the inner corner of the eye for one to two minutes and blot away any excess drops to help minimise absorption into your system.

Corticosteroid nasal sprays containing budesonide and mometasone can give some symptom relief by reducing inflammation in the nose. Because these medications act locally at the nose and are likely to enter the mother’s bloodstream in very small amounts only, they are considered safe in pregnancy.

Decongestant nasal sprays (see cold and flu) may be used short term if corticosteroid and antihistamine nasal sprays have not relieved the symptoms.

 

Aches and pains

Paracetamol is considered safe to use in pregnancy and is effective in treating aches, pains and fever. It is important that no more than 8 tablets (containing 500mg of paracetamol) are taken within a 24-hour period.

Anti-inflammatory medicines - including topical preparations e.g., creams are NOT recommended in pregnancy (especially in the third trimester).

If paracetamol is inadequate or unsuitable, short-term use of some opioid medicines to treat moderate to severe pain is considered safe to use in pregnancy. Regular use of these medicines late in pregnancy can cause newborn withdrawal symptoms, so it is important to inform your healthcare providers of their use. These medicines can also lead to dependency and, if used consistently, can become less effective. It is necessary to consult your doctor if opioid pain relief is required.

 

Cold and flu

Common colds are caused by a virus and often include symptoms such as sore throat, cough, runny and / or blocked nose, sneezing, body aches, mild headache and general tiredness. Colds typically resolve on their own and usually only require treatment for individually bothersome symptoms.

Sore throat
A sore throat can be relieved by drinking warm lemon and honey drinks or gargling warm, salty water. Lozenges containing antibacterial and anaesthetic (numbing) agents are considered safe to use in pregnancy at recommended dosages. Medicines containing benzydamine (anti-inflammatory) should not be used in pregnancy unless under the direction of a doctor. Gargles containing povidone-iodine should be avoided as there is a risk that it may affect the thyroid of the developing fetus.

Cough
For a dry, tickly cough, dextromethorphan is considered safe to use in pregnancy. It provides relief by suppressing the cough while the immune system recovers from the virus. For a chesty, productive cough, medicines such as bromhexine and guaifenesin are considered safe to use in pregnancy. They provide relief by facilitating the removal of mucus from the chest.

Runny or blocked nose
A runny nose can be treated with oral sedating antihistamine medicines (see hay fever and allergies). A blocked nose can be treated with decongestant nasal sprays (oxymetazoline or xylometazoline), saline nasal sprays or steam inhalation. Very small amounts of these medicines are expected to absorb into the body from nasal sprays, therefore, they are considered safe to use in pregnancy. Decongestant nasal sprays should not be used for more than three days at a time due to the risk of rebound congestion. Oral medicines to treat a blocked nose, such as pseudoephedrine or phenylephrine, are not recommended in pregnancy.

 

Constipation

Constipation is very common in pregnancy and eating high-fibre foods, such as wholegrain cereals and bread, fresh fruits and vegetables, along with drinking plenty of fluids, regularly exercising and going to the toilet as soon as you feel the urge, help to maintain regular bowel motions in pregnancy.

Fibre supplements (bulk-forming laxatives) such as psyllium, sterculia and ispaghula are suitable to use with plenty of water. Osmotic laxatives such as macrogol, lactulose and sorbitol draw water into the bowel and help to soften the stool. A stool softener such as docusate is also safe to use in pregnancy but the use of stimulant laxatives such as senna and bisacodyl are not recommended for regular use.

Medicines taken in pregnancy such as antacids for heartburn, strong pain medicines, multivitamins, iron and calcium tablets, or nausea and vomiting can make constipation worse.

 

Reflux / heartburn

Heartburn can develop in up to 80 percent of pregnant women. In late pregnancy, this is made worse by the increasing pressure of the baby on the stomach. Dietary and lifestyle measures, such as eating smaller, more frequent, meals; avoiding spicy and highly fatty foods; not lying down immediately after a meal or eating late at night, may help to reduce symptoms.

If these measures are not working, then oral liquid antacids (eg: Gaviscon®, Gastrogel®) can be tried at the recommended dosages. A group of medicines called H₂ Antagonists (eg: Famotidine) are considered safe to use in pregnancy if antacids are ineffective. Another group of medicines called proton pump inhibitors (PPIs), such as omeprazole, may be considered for use.

 

Haemorrhoids

Haemorrhoids are swollen and enlarged veins in the anus and rectum that can be either internal, external or a combination of the two. They are common in pregnancy and can be triggered by pressure from the uterus, hormone changes and constipation. The best way to manage haemorrhoids is with lifestyle modifications such as:

• Taking a warm bath
• Applying ice packs to external haemorrhoids to reduce pain and swelling
• Ensuring adequate fibre and fluid intake (see constipation above)
• Trying not to strain during bowel movements and going to the toilet when the urge is felt

In some cases, haemorrhoids can cause discomfort that interferes with quality of life. In these circumstances, they can be treated with suppositories/ointments containing an anaesthetic and/or steroid (eg:. Proctosedyl®, Rectinol®), which are considered safe to use in pregnancy. These can be used up to three times a day and are best applied after a bowel motion - for no longer than seven days.

 

Vaginal thrush

Vaginal thrush is one of the most common fungal infections during pregnancy. Typical symptoms include itching, stinging, burning, and a thick, white, vaginal discharge.

Vaginal antifungal creams and pessaries containing clotrimazole or nystatin are considered safe during pregnancy and are the treatments of choice. Vaginal applicators may be used with care in pregnancy.

At least a six-day course of clotrimazole or a 14-day course of nystatin is recommended in pregnancy, rather than a shorter course.

A single dose of oral fluconazole is not routinely recommended during pregnancy unless it is advised by your doctor.

 

Cold sores

Cold sores occur commonly during pregnancy and are not thought to affect the unborn baby. Ice is a recommended treatment for cold sores and can be applied to the affected area.

Antiviral medicines such as aciclovir cream can be used safely at all stages of pregnancy. If the cold sores are severe, an oral course of aciclovir or valaciclovir from your doctor would be considered safe to use at all stages of pregnancy.

Avoiding triggers such as sun and wind exposure, stress, or certain food and drinks can reduce the likelihood of an outbreak. Using lip balms with SPF15+ can also minimise your risk of cold sores.

 

Nausea and vomiting

See Nausea and vomiting in pregnancy (PDF)

 

Herbals

There is very little information available on the safety of herbal preparations in pregnancy, or their effect on your baby. Care should be exercised with their use. Talk to your doctor or pharmacist to discuss your options and for further advice.

 

Vitamins

Having a well-balanced, healthy diet is important during pregnancy to ensure you and your baby’s needs are met. Vitamins such as folic acid, iron, vitamin D and iodine are especially important during your pregnancy. For more information see Chapter 3 ‘Taking care of yourself’ Pregnancy, birth and your baby (PDF).

 

COVID-19 and flu vaccine

The Comirnaty Pfizer®, SpikeVax Moderna®, Nuvaxovid NovaVax® and annual influenza vaccines are considered safe in pregnancy. These vaccines are recommended for women who are pregnant.

 

---

 

References

1. MotherSafe Factsheets | South Eastern Sydney Local Health District (external site)
2. A-Z fact sheets | The Royal Women's Hospital (external site)
3. Bumps Leaflets A to Z - best use of medicine in pregnancy (external site)
4. Fact Sheets | MotherToBaby (external site)