How to accurately assess and treat nausea and vomiting during pregnancy

Vomiting during pregnancy is one of the most common symptoms in pregnant women. It mainly occurs in the first three months of pregnancy, but for some patients it may last throughout the pregnancy and affect the quality of life. So how should vomiting during pregnancy be treated?

Non-drug treatment

Dietary modification

Dietary modification is the basis of NVP treatment. Eat small meals frequently; light and low-fat; high-protein, low-sugar; liquid diet; drink small amounts of water between meals, and choose drinks containing electrolytes; if hot meals trigger nausea, choose cold meals if necessary.

Ginger

The American College of Obstetricians and Gynecologists recommends ginger as a non-pharmacological means of treating NVP. A large number of studies have also shown that ginger can be used to improve symptoms and is relatively safe for the fetus; however, because ginger can inhibit platelet function, it is not recommended for patients receiving anticoagulant therapy.

Acupressure and acupuncture

Studies have shown that pressing or acupuncture on the Neiguan acupoint can relieve nausea and retching; the effect of acupuncture on improving symptoms in pregnant women with HG is comparable to that of metoclopramide and vitamin B12. These data suggest that acupressure and acupuncture may be helpful in the treatment of NVP, but their benefits remain uncertain.

Vitamin B1 supplementation

It is very meaningful for pregnant women with HG to supplement vitamin B1. Thiamine pyrophosphate is the biologically active form of vitamin B1 and an important coenzyme for various biochemical processes in the brain. The daily requirement of vitamin B1 for women is about 1.1 mg, which can be increased to 1.5 mg during pregnancy. It can be further increased in pregnant women with HG because absorption is affected.

Intravenous fluids

Pregnant women with HG who are severely dehydrated or even have ketoacidosis are generally recommended to be hospitalized, and immediate rehydration can relieve most symptoms. At the same time, parenteral nutrition and supplementation of vitamins and trace elements can help correct electrolyte imbalances. Adding glucose during fluid replacement can provide energy support.

Drug treatment

Antihistamines

Antihistamines are often used to treat nausea and vomiting during early pregnancy. The first-generation H1 receptor antagonists diphenhydramine, dimenhydrinate, meclizine, and pheniramine can indirectly affect the vestibular system and reduce stimulation of the vomiting center. These antihistamines are all Category B medications for use during pregnancy and have been shown to be effective in controlling NVP symptoms.

The American College of Obstetricians and Gynecologists recommends the above drugs alone or in combination with vitamin B6 for the first-line treatment of NVP. In April 2013, the U.S. Food and Drug Administration (FDA) approved Diclegis for the treatment of NVP in pregnant women. It is an extended-release tablet containing 10 mg of doxylamine succinate and 10 mg of vitamin B6 hydrochloride. The most common adverse reaction of this drug is drowsiness.

Antiemetics

Central and peripheral dopamine antagonists chlorpromazine and prochlorperazine can also alleviate the symptoms of NVP and HG. Both are pregnancy category C medications, used during the first three months of pregnancy when the risk of birth defects is slightly increased. Another phenothiazine drug, promethazine, is also widely used in many countries and regions and is also a Category C medication for pregnancy. Although studies have shown that it has no teratogenic effects, it has anticholesterol effects such as dry mouth, drowsiness, and sedation. Therefore, it can be considered as a second-line treatment for NVP.

Benzamides

Metoclopramide is a dopamine and 5-hydroxytryptamine receptor antagonist that is widely used in the treatment of NVP. It is a Class B drug for pregnancy and is safe to use, but it has adverse reactions such as drowsiness and dizziness, and long-term use carries the risk of tardive dyskinesia, so it can be considered as a third-line drug for NVP.