Antiemetics

Of all pregnant women, 50-80% suffers from nausea and vomiting of pregnancy (NVP), also known as morning sickness-although symptoms may persist throughout the whole day. Usually limited to the first trimester, NVP may continue for the entire pregnancy. NVP may range from mild discomfort to severe vomiting and nausea, weight loss, dehydration and metabolic compromise. In severe cases, NVP can be fatal. NVP poses a serious socioeconomic burden, as 25% of women suffering from NVP miss work as a result of their symptoms. The pathogenesis of NVP has been attributed to multiple factors such as elevated levels of prostaglandin levels (by relaxing the gastroesophageal sphincter), gastric dysrhythmia, vitamin B6 deficiency, and hyperolfaction. The chapter discusses the diet manipulations and treatment that can curb NVP, along with some complementary treatment options, such as acupuncture and acupressure, hypnosis, and the consumption of ginger. First- and second-generation antihistamines, especially Doxylamine in combination with vitamin B6 are a safe and effective treatment for NVP. Dopamine antagonists are also widely used for treatment of NVP, especially in countries where Benedictine is unavailable. Apart from these, pyridoxine, thiamine, serotonin antagonists, and glucocorticoids can be used to treat NVP; their pharmacology and toxicology are explained in the chapter.