If dehydration is present due to loss of fluids from severe vomiting, rehydration with oral electrolyte solutions is preferred. If this is not effective or possible, intravenous rehydration may be required. Medical care is recommended if: a person cannot keep any liquids down, has symptoms more than 2 days, is weak, has a fever, has stomach pain, vomits more than two times in a day or does not urinate for more than 8 hours. Medications Many pharmacologic medications are available for the treatment of<unk> . There is no medication that is clearly superior to other medications for all cases of<unk> . The choice of antiemetic medication may be based on the situation during which the person experiences<unk> . For people with motion sickness and vertigo, antihistamines and anticholinergics such as meclizine and scopolamine are particularly effective.<unk>  and vomiting associated with migraine headaches respond best to dopamine antagonists such as metoclopramide, prochlorperazine, and chlorpromazine. In cases of gastroenteritis, serotonin antagonists such as ondansetron were found to suppress<unk>  and vomiting, as well as reduce the need for IV fluid resuscitation. The combination of pyridoxine and doxylamine is the first line treatment for pregnancy-related<unk>  and vomiting. Dimenhydrinate is an inexpensive and effective over the counter medication for preventing postoperative<unk>  and vomiting. Other factors to consider when choosing an antiemetic medication include the person's preference, side-effect profile, and cost. Nabilone is also indicated for this purpose. Alternative medicine In certain people, cannabinoids may be effective in reducing chemotherapy associated<unk>  and vomiting. Several studies have demonstrated the therapeutic effects of cannabinoids for<unk>  and vomiting in the advanced stages of illnesses such as cancer and AIDS. In hospital settings topical anti-nausea gels are not indicated because of lack of research backing their efficacy. Topical gels containing lorazepam, diphenhydramine, and haloperidol are sometimes used for<unk>  but are not equivalent to more established therapies. Ginger has also been shown to be potentially effective in treating several types of<unk> .
Nausea
Vomiting
Constipation
Flushing 
Fever
Allodynia
Arthralgia
Myalgia