Vomiting motion sickness

Advantages are that a drug that is irritant to the stomach can be given by suppository (aminophylline, indomethacin) the route is suitable in vomiting, motion sickness, migraine or when a patient cannot swallow, and when cooperation is lacking (sedation in children). 

Clinical uses Symptomatic relief of seasonal allergies, nausea and vomiting, motion sickness, transfusion reactions, pruritis, edema, and urticaria associated with allergic reactions. 

Indications Dizziness, tinnitus, nystagmus, nausea and vomiting, motion sickness... 

This compound has antihistaminic activity and is usehil in the therapy of motion sickness. It may also be effective in the control of post-operative nausea and vomiting. It is classified as FDA Category B for Pregnancy, ie, no demonstrated risks shown in animal studies however, no controlled trials in pregnant women. Large doses may cause drowsiness and dry mouth owing to decreased secretion of saUva. 

Impulses from the vestibular apparatus in the labyrinth are conducted via the vestibular nucleus and cerebellum to the vomiting centre. Abnormal stimulation of the vestibular apparatus is involved in motion sickness and emesis, associated with Menieres disease. 

Several histamine receptor antagonists are effective in treating motion sickness, Meniere s disease, morning sickness, uraemia and postoperative vomiting. They are not effective against cytotoxics. Antagonists with... 

These include atropine, scopolamine (hyoscine), trihexyphenidyl (benzhexol) and benzatropine. They block central muscarinic receptors involved in various afferent pathways of the vomiting reflex (Fig. 1). They have been used to control motion sickness, emesis in Meniere s disease and postoperative vomiting. Currently, hyoscine is largely restricted to the treatment of motion sickness where it has a fast onset of action but a short duration (4-6 h). Administration of hyoscine by transdermal patch produces a prolonged, low-level release of the drug with minimal side effects. To control postoperative vomiting, it should be applied >8 h before emesis is anticipated. 

It is important to note diat antivertigo dragp are essentially antiemetics because many of these preparations, whedier used for motion sickness or vertigo, also have direct or indirect antiemetic properties. They prevent the nausea and vomiting diat occur because of stimulation of die vestibular apparatus in the ear. Stimulation of diis apparatus results in vertigo, which is often followed by nausea and vomiting. 

Emesis No distinct pathway DA receptors in chemoreceptor pathway zone Vomiting Anti-emetic (not motion sickness) D2 ... 

Recommend a treatment regimen for a patient with nausea and vomiting associated with cancer chemotherapy, surgery, pregnancy, or motion sickness. 

Motion sickness is caused by stimulation of the vestibular system. This area contains many histaminic (Hj) and muscarinic cholinergic receptors. The higher brain (i.e., cerebral cortex) is affected by sensory input such as sights, smells, or emotions that can lead to vomiting. This area is involved in anticipatory nausea and vomiting associated with chemotherapy. 

Antihistamines are commonly used to prevent and treat nausea and vomiting due to motion sickness, vertigo, or migraine headache.1,17 Their efficacy is presumably due to the high concentration of histamine (Hx) and muscarinic cholinergic receptors within the vestibular system. Similarly to scopolamine, antihistamines such as diphenhydramine and... 

A 28-year-old healthy woman seeks your advice. She is about to leave on a 7-day Caribbean cruise and is concerned about motion sickness. She recently experienced nausea and one episode of vomiting while on a sailboat on Lake Michigan for an afternoon. She is not allergic to any medications. She does not smoke and only occasionally drinks alcohol. She takes an oral contraceptive (ethinyl estradiol and norgestimate) and occasional ibuprofen for headaches. 

Applied to the skin in a transdermal patch (tra ns dermal therapeutic delivery systemX this drug is used to prevent or reduce the occurrence of nausea and vomiting that are associated with motion sickness. 

The answer is e. (Hardmanr p 930.) All the drugs listed in the question are used as antiemetics. Chlorpromazine is a general antiemetic, used orally, rectally, or by injection for the control of nausea and vomiting that is caused by conditions that are not necessarily defined. Ondansetron is indicated in the oral or intravenous route for the prevention of nausea and vomiting caused by cancer chemotherapy Diphenhydramine and dimen-hydrinate are used orally for the active and prophylactic treatment of motion sickness. Scopolamine is a transdermal preparation used in the prevention of motion sickness. The drug is incorporated into a bandage-like... 

Metoclopramide is ineffective in motion sickness, as it acts selectively on the chemoreceptor trigger zone. Metoclopramide is effective in treating vomiting associated with gastroduodenal, biliary and hepatic disease, and postoperative vomiting. 

Domperidone is a dopamine antagonist that acts on the chemoreceptor trigger zone. It can therefore be used as an anti-emetic in nausea and vomiting, for example, to counteract side-effects of cytotoxic therapy and to treat nausea associated with dopaminergic drugs used in Parkinson s disease. Unlike hyoscine butlybromide and antihistamines, domperidone is ineffective in motion sickness. 

Promethazine Promethazine also is indicated for preoperative, postoperative, or obstetric sedation prevention and control of nausea and vomiting associated with certain types of anesthesia and surgery an adjunct to analgesics for control of postoperative pain sedation and relief of apprehension, and to produce light sleep antiemetic effect in postoperative patients active and prophylactic treatment of motion sickness (oral and rectal only). 

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