Reproductive health
Medicines for Hyperemesis gravidarum
Severe, persistent nausea and vomiting in pregnancy that goes far beyond normal "morning sickness", causing dehydration, weight loss and an inability to keep food and fluids down — it is not something to simply put up with, and it needs active treatment with anti-sickness medicines, fluids and vitamin replacement.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Hyperemesis gravidarum?
Hyperemesis gravidarum is severe, persistent nausea and vomiting in pregnancy. It is at the far end of a spectrum that begins with the common "morning sickness" many women experience in early pregnancy — but it is much more than that.
- How it is treated: The aim of treatment is to control the nausea and vomiting, correct and prevent dehydration, and protect a woman's nutrition and wellbeing through what can be a very difficult time.
- Self-care: While hyperemesis needs medical treatment, some practical measures can help alongside it: resting as much as possible, eating little and often when you can manage it, sipping fluids in small amounts frequently rather than large drinks, and avoiding smells or foods that trigger nausea.
- When to seek help: Contact your midwife, GP or maternity unit promptly if you have severe or persistent vomiting in pregnancy — and do so without delay if you cannot keep any fluids down, are passing very little or dark urine, feel dizzy or faint, are losing weight, or simply feel very unwell.
What it is
Hyperemesis gravidarum is severe, persistent nausea and vomiting in pregnancy. It is at the far end of a spectrum that begins with the common "morning sickness" many women experience in early pregnancy — but it is much more than that. With hyperemesis, the sickness is relentless and overwhelming, making it impossible to keep food or even fluids down, and it can lead to dehydration, weight loss and feeling utterly drained and unwell. It usually starts in the first few weeks of pregnancy and, for some women, continues well beyond the first trimester. The exact cause is not fully understood, but pregnancy hormones are thought to play a major part. The crucial message is that hyperemesis gravidarum is a recognised medical condition that needs active treatment — it is not something a woman should be expected to "just put up with" or tough out. Left untreated it can make a woman seriously unwell and have a real impact on her physical health and wellbeing during what should be an exciting time. With the right care, including anti-sickness medicines and fluid and vitamin replacement, the great majority of women can be helped to feel much better.
How it is treated
The aim of treatment is to control the nausea and vomiting, correct and prevent dehydration, and protect a woman's nutrition and wellbeing through what can be a very difficult time. Anti-sickness medicines (antiemetics) are a central part of care; those used in pregnancy are chosen to be as safe as possible for both mother and baby, and there is a recognised order in which different options are tried. These are used alongside measures to keep a woman hydrated — encouraging small, frequent sips where possible, and giving fluids directly into a vein (intravenous, or IV, fluids) in hospital when a woman cannot keep anything down. Replacing vitamins, particularly thiamine (vitamin B1), is important to prevent complications when eating and drinking have been poor. Throughout, signs of dehydration and the level of ketones (a marker that the body is breaking down fat for energy because it is not getting enough) are monitored, often with urine and blood tests, to guide how much support is needed. Many women can be managed with treatment at home or as a day case, while those who are more severely affected may need to be admitted to hospital for IV fluids and closer care until things settle.
For this condition, these medicines
Medicine classes used for Hyperemesis gravidarum
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Symptom checker
Symptoms that can point to Hyperemesis gravidarum
Hyperemesis gravidarum can be one cause of these symptoms. Each guide explains the other possible causes and the red-flag warning signs that mean you should get urgent help:
Beyond medication
Lifestyle and self-care
While hyperemesis needs medical treatment, some practical measures can help alongside it: resting as much as possible, eating little and often when you can manage it, sipping fluids in small amounts frequently rather than large drinks, and avoiding smells or foods that trigger nausea. Getting support with daily life and not trying to soldier on alone matters too. None of these replace anti-sickness medicines and fluids when sickness is severe — they sit alongside proper treatment rather than instead of it.
When to get help
When to see a doctor
Contact your midwife, GP or maternity unit promptly if you have severe or persistent vomiting in pregnancy — and do so without delay if you cannot keep any fluids down, are passing very little or dark urine, feel dizzy or faint, are losing weight, or simply feel very unwell. These are signs of dehydration and that you need active treatment, which may include anti-sickness medicines and, if you cannot keep fluids down, fluids given into a vein in hospital. Please do not feel you should "just put up with it" or wait to see if it passes — hyperemesis gravidarum is a recognised condition that deserves treatment, and asking for help early can stop you becoming more unwell. If you cannot reach your usual maternity contacts and feel very unwell, seek urgent medical care.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Hyperemesis gravidarum: frequently asked questions
What medicines are used for hyperemesis gravidarum?
Anti-sickness medicines, known as antiemetics, are the main treatment, and importantly they should be used — hyperemesis is not something to leave untreated. The medicines chosen for use in pregnancy are selected to be as safe as possible for both mother and baby, and there is a recognised order in which different options are tried if the first does not work well enough. They are used alongside other essential measures: keeping you hydrated, including fluids given into a vein in hospital if you cannot keep anything down, and replacing vitamins such as thiamine (vitamin B1). Your midwife, GP or maternity team will guide which medicines are right for you and adjust treatment as needed.
How is hyperemesis different from normal morning sickness?
Morning sickness — nausea and sometimes vomiting in early pregnancy — is very common and, while unpleasant, most women can still eat, drink and carry on with daily life. Hyperemesis gravidarum sits at the severe end of the scale. The sickness is relentless and overwhelming, making it impossible to keep food or even fluids down, and it leads to dehydration, weight loss and feeling drained and very unwell. It needs active medical treatment rather than self-care alone. If your sickness is stopping you keeping fluids down, causing weight loss, or making you feel very unwell, it has gone beyond ordinary morning sickness and you should seek help.
Is hyperemesis gravidarum harmful to my baby?
The most important step is getting the condition treated, which protects both you and your baby. Untreated severe sickness can leave you dehydrated and undernourished and can make you seriously unwell, which is why active treatment with anti-sickness medicines, fluids and vitamin replacement is so important. The anti-sickness medicines used in pregnancy are chosen specifically to be as safe as possible for the baby, and the benefits of keeping you well and hydrated are central. Try not to worry alone — speak to your midwife, GP or maternity team, who can reassure you, treat the sickness and monitor things closely.
Will I need to go to hospital?
Not necessarily — many women can be managed at home or as a day case with anti-sickness medicines and advice on staying hydrated. However, hospital care, including fluids given directly into a vein (IV fluids), is needed when you cannot keep any fluids down, are becoming dehydrated, or are losing weight and feeling very unwell. Being admitted allows the team to rehydrate you, control the sickness and replace vitamins until things settle, and it is a normal and helpful part of caring for more severe hyperemesis. The key is to seek help early, so that treatment can start before you become more unwell.
Sources
Where this is drawn from
- Pregnancy Sickness Support: Hyperemesis gravidarum.
- Royal College of Obstetricians and Gynaecologists: The management of nausea and vomiting of pregnancy and hyperemesis gravidarum.
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