Motion sickness, treatment

C. Ginkgo would be the most likely herbal treatment to benefit this patient, since it would improve cerebrovascular blood flow and cognitive function. Vertigo and tinnitus may also respond, although there is more evidence for the former. GarUc is traditionally used for cardiovascular benefits (Upid, blood pressure reduction), but it would be unlikely to produce immediate results. Peppermint is used as an antispasmodic in irritable bowel syndrome, while ginger tea is a common carminative (gas reducer) and motion sickness treatment. Valerian is useful as a sedative. 

Use Prevention and treatment of nausea, vomiting, vertigo due to motion sickness. Treatment of vertigo associated with diseases affecting vestibular system. Half-life 6 hours Onset 30-60 minutes Peaks Duration 10 hours 12-24 hours... 

Despite the limitations imposed by the physiology of the skin, several marketed controUed release transdermal dmg dehvery systems are available in the United States for example, scopolamine [51-34-3] for the treatment of motion sickness, nitroglycerin [55-63-0] for angina, estradiol [50-28-2] for the rehef of postmenopausal symptoms and osteoporosis, clonidine [4205-90-7] for the treatment of hypertension, fentanyl [437-38-7] as an analgesic, and nicotine [54-11-5] as an aid to smoking cessation. These systems are designed to dehver dmg for periods of one to seven days. 

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. 

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

Diphenhydramine Diphenhydramine also is indicated for active treatment of motion sickness (injection only) for parkinsonism in the elderly intolerant of more potent agents, for mild cases in other age groups, and in combination with centrally... 

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). 

Motion sickness, vestibuiar system disease Prevention and treatment of nausea, vomiting, and dizziness of motion sickness. 

Treatment and prophylaxis (oral only) of motion sickness. 

Furthermore, central-acting antimuscarinic drug are effective in the treatment of motion sickness. In this indication the alkaloid scopolamine has been shown to be effective. It can be applied orally, intra venously or via a transdermal therapeutic system. 

Another important use of Hj-antagonists is in the treatment of motion sickness. Diphenhydramine (Benadryl), dimenhydrinate (Dramamine), cyclizine (Marezine), and meclizine (Antivert) have anticholinergic activity and are the preferred antihistaminic agents for reducing the symptoms of motion sickness. 

B. Although scopolamine effectively combats motion sickness, it is an antimuscarinic agent, not an antihistamine. Dimenhydrinate is an antihistamine with signihcant antimuscarinic properties that are likely to contribute to its anti-motion sickness activity. Chlorpheniramine, fexofenadine, and tripelennamine are antihistamines without signihcant efficacy in the treatment of motion sickness. 

CNS disorders Scopolamine and hyoscine are effectively used in the treatment of nausea, vomiting and motion sickness. Centrally acting anticholinergic/ antihistaminics e.g. trihexyphenidyl are used in parkinsonism. 

The prototype antihistamine of this group is diphenhydramine. It has antimuscarinic and pronounced central sedative properties and also an antitussive effect. The mechanism of the latter is unclear, but diphenhydramine is a common ingredient of propriety preparations for the treatment of coughs and colds. It is an effective anti-emetic, especially useful for prevention and treatment of motion sickness. Because of its anticholinergic properties it is occasionally used in the treatment of mild forms of Parkinson s disease. It is also of use in the treatment of drug-induced extrapyramidal effects. Piperazine derivatives... 

Cinnarizine is an H 1-receptor antagonist and a calcium channel blocker used for the treatment of vertigo and emetic symptoms due to Meniere s disease and related labyrinth disorders. It is also effective in motion sickness. It is used for peripheral and cerebral vascular disorders, because of its calcium channel blocking properties. 

Promethazine has prominent sedative effects as weii as anti-muscarinic and dopamine D2-blocking effects. These make it usefui as an anti-emetic, and it is especially useful for the prevention and treatment of motion sickness. Like other phenothiazines, it has weak al-adrenergic blocking effects and can iower biood pressure if injected rapidly intravenously. Intramuscular injection can be painful. Alimemazine tartrate is a phenothiazine with HI antagonist activity that produces marked sedation. It is used mainiy for its marked relief of pruritus, and is also popular for the premedication of children (dose 2 mg-kg-1). 

Dimenhydrinate, which is promoted almost exclusively for the treatment of motion sickness, is a salt of diphenhydramine. The piperazines (cyclizine and meclizine) also have significant activity in preventing motion sickness and are less sedating than diphenhydramine in most patients. Dosage is the same as that recommended for allergic disorders (Table 16-2). Both scopolamine and the Hi antagonists are more effective in preventing motion sickness when combined with ephedrine or amphetamine. 

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