Xonvea Side Effects

If you’ve been prescribed Xonvea for pregnancy sickness, you’re probably wondering what to expect when you start taking it. While it’s very effective at easing nausea and vomiting, like all medicines, it may cause side effects in some people. 

We’ll walk you through the most common side effects of Xonvea and what to do about them, so you can feel confident in managing your treatment. 

Three key takeaways 

• Xonvea is safe to take during pregnancy and has mild side effects, meaning it’s very well tolerated.  

• Common side effects of Xonvea include sleepiness and tiredness, dizziness, and a dry mouth. 

• If you’re experiencing side effects with Xonvea, speak to your prescriber, GP, or midwife for advice. 

Is Xonvea safe?

Yes, Xonvea is safe to take during pregnancy. The ingredients (doxylamine and vitamin B6) have been studied extensively over the years, with Xonvea being recommended as a first-line treatment for pregnancy sickness.

There was no increased risk of birth defects, miscarriage, stillbirth, or premature birth.

Most common Xonvea side effects

Very common (may affect more than one in 10 people) side effects of Xonvea include:

• feeling sleepy

Common (may affect up to one in 10 people) side effects include:

• feeling dizzy
• feeling tired
• dry mouth

As the most common side effects of Xonvea can compromise your mental awareness (tiredness and dizziness), you shouldn't drive or perform skilled tasks until you know how the treatment affects you individually.

How to deal with Xonvea side effects

“While taking Xonvea and dealing with pregnancy sickness, it’s important to give yourself permission to rest and not push yourself too hard. The medication can make you feel tired and dizzy, and when you combine that with the exhaustion of pregnancy and sickness, it’s a lot for your body to handle.  

“Pushing through to maintain your usual schedule can make your nausea and vomiting worse.  

“Listen to what your body is telling you. Whether it’s going to bed earlier, taking naps, asking for help with daily tasks, or simply lowering your expectations of what you can currently manage, taking it easy is one of the best things you can do for yourself and your baby.” 

Dr Rashi Malhotra, General Practitioner 

Other side effects of Xonvea

While there are other potential side effects of Xonvea, they’re uncommon. Most people who do experience other side effects find that they’re mild. 

That being said, it’s worth knowing what else to look out for so you can make an informed decision about your treatment. 

Other Xonvea side effects may include: 

• anxiety 

• difficulty sleeping (insomnia), nightmares, disorientation 

• headaches or migraines 

• tingling, pricking, or numbness of the skin 

• restlessness 

• problems with eyesight or blurred/double vision 

• sensation of spinning (vertigo) 

• difficulty breathing, awareness of heartbeat, or increased heart rate (tachycardia) 

• stomach pain, constipation, or diarrhoea 

• excessive sweating, skin reactions (itchiness or rash) 

• difficulty or pain with passing urine (dysuria) or inability to empty bladder 

• chest discomfort 

• general discomfort, feeling irritable 

How Chemist4U is increasing access to Xonvea

We understand how much pregnancy sickness can impact your life. But with access to a first-line treatment like Xonvea being a postcode lottery, something needs to change. 

That's why we're not only offering Xonvea at an affordable price but making access easier for those who need it.  

We know that leaving the house when you're battling nausea and vomiting can feel impossible. 

So, all you need to do is answer some questions about your symptoms and medical history online, and if suitable, we'll deliver it directly and discreetly to your door.  

Frequently asked questions about Xonvea side effects 

Is Xonvea safe to use in the first trimester? 

Xonvea is safe to use in the first trimester. In fact, this is when it’s most commonly used, as pregnancy sickness usually starts within the first six weeks. The active ingredients in Xonvea have been studied extensively, and there’s no increased risk to your baby. 

How long does it take for Xonvea to work?  

Most people start to notice an improvement in their symptoms within a few days of taking Xonvea. It’s important to take it consistently and as prescribed, even if you don’t feel better right away. If you’re not seeing any improvement after a week, speak to your prescriber, GP, or midwife. 

Are there any alternatives to Xonvea? 

Yes, there are other treatments available for pregnancy sickness. These include antihistamines like cyclizine or promethazine, or anti-sickness medications like metoclopramide or ondansetron. 

Sources

• Nausea and Vomiting in Pregnancy Research. (2014). PMC/NCBI. [Accessed 3rd December 2025]. 
• Use of Xonvea in Pregnancy. (2025). UK Teratology Information Service. [Accessed 3rd December 2025]. 
• Xonvea Patient Information Leaflet. Medicines.org.uk. [Accessed 3rd December 2025]. 
• Doxylamine with Pyridoxine. British National Formulary. [Accessed 3rd December 2025]. 
• Use of Xonvea in Pregnancy. (2025). UK Teratology Information Service. [Accessed 3rd December 2025]. 
• Medications and Treatments for Pregnancy Sickness. Pregnancy Sickness Support. [Accessed 3rd December 2025]. 
• Cyclizine: Pregnancy, Breastfeeding and Fertility. (2022). NHS. [Accessed 3rd December 2025]. 
• Promethazine Prescribing Information. (2025). NICE Clinical Knowledge Summaries. [Accessed 3rd December 2025]. 

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