From the Guidelines
Hyperemesis gravidarum should be managed with a step-up approach, starting with vitamin B6 supplementation as first-line treatment, and considering metoclopramide or ondansetron as second-line therapies for patients who do not respond to initial treatment. The goals of management are to prevent dehydration, correct electrolyte abnormalities, and support adequate maternal and fetal nutrition 1. Treatment is guided by the severity of symptoms and may require a multidisciplinary team approach involving obstetricians, nutritionists, psychologists, and gastroenterologists.
Key Considerations
- Laboratory evaluation should focus on the extent of dehydration, nutritional or vitamin deficiencies, and electrolyte imbalances 1.
- Ultrasonography of the abdomen can help detect multiple or molar pregnancies and adequate fetal growth, and rule out hepatobiliary, vascular, or renal explanations for the symptoms 1.
- Mental health care professionals can help manage anxiety, depression, and other emotional challenges associated with hyperemesis gravidarum 1.
- Vitamin B1 (thiamine) should be given to prevent refeeding syndrome and Wernicke encephalopathy, starting with a dosage of 100 mg daily for a minimum of 7 days 1.
Treatment Options
- Vitamin B6 (pyridoxine) may be suggested as a first-line treatment for mild cases 1.
- Metoclopramide can be given for nausea and vomiting, with a similar efficacy to promethazine but fewer adverse events 1.
- Ondansetron can be given primarily in severe cases that require hospitalization, but should be used with caution in the first trimester due to potential risks of congenital heart defects 1.
- Methylprednisolone can be given as a last resort in patients with severe hyperemesis gravidarum, but should be administered with caution in the first trimester due to potential risks of cleft palate 1.
From the Research
Definition and Prevalence of Hyperemesis Gravidarum
- Hyperemesis gravidarum (HG) is a severe and prolonged form of nausea and/or vomiting during pregnancy, affecting 0.3-2% of pregnancies 2.
- It is defined by dehydration, ketonuria, and more than 5% body weight loss 2.
- HG is a significant source of morbidity and one of the most common indications for hospitalization in pregnancy, affecting 0.3-1.0% of pregnancies 3.
Treatment Options for Hyperemesis Gravidarum
- Initial pharmacologic treatment for HG includes a combination of doxylamine and pyridoxine 2.
- Additional interventions include ondansetron or dopamine antagonists such as metoclopramide or promethazine 2.
- Mirtazapine is a useful drug in the context of HG, acting on noradrenergic, serotonergic, histaminergic, and muscarinic receptors to produce antidepressant, anxiolytic, antiemetic, sedative, and appetite-stimulating effects 2.
- There is evidence that ginger, antihistamines, metoclopramide (mild disease), and vitamin B6 (mild to severe disease) are better than placebo in treating HG 4.
- Diclectin (doxylamine succinate plus pyridoxine hydrochloride) is more effective than placebo and ondansetron is more effective at reducing nausea than pyridoxine plus doxylamine 4.
Effectiveness of Antiemetics in Treating Hyperemesis Gravidarum
- A comparison between metoclopramide and ondansetron identified no clear difference in the severity of nausea or vomiting, but more women taking metoclopramide complained of drowsiness and dry mouth 3.
- There were no clear differences between groups for other side effects, and other factors such as side effect profile, medication safety, and healthcare costs should be considered when selecting an intervention 3.
- The use of oral pyridoxine in conjunction with metoclopramide during the inpatient stay and during the 2 weeks after hospital discharge for hyperemesis gravidarum did not improve the rehospitalization rate, the vomiting frequency, or the nausea score 5.
Impact of European Warning on Metoclopramide
- The European Medical Agency (EMA) issued a warning on metoclopramide in 2013, limiting treatment to a maximum of five days 6.
- Following the EMA warning, prehospital use of metoclopramide dropped by 30%, while use of any antiemetic pre-hospital dropped by 20% 6.
- This led to a decrease in gestational age at first admission and an indication of increased rate of termination of pregnancy 6.