Motion sickness patches

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. 

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. 

Certain plants of the family Solanaceae, such as Atropa belladonna L., Hyoscyamus niger L., and Datura stramonium L., have been used medicinally for centuries in Europe because they contain tropane-type alkaloids.For example, atropine (1) [a racemic mixture of (+)- and (—)-hyoscyamine (2)] and (-)-hyoscyamine are competitive antagonists at the muscarinic acetylcholine receptor site, leading to antispasmodic and antiallergic effects. Scopolamine [(—)-hyoscine)] (3) is used in a transdermal patch for the prevention of motion sickness. Since these tropane alkaloids penetrate the blood-brain barrier, they also have psychoactive effects. ... 

Scopolamine inhibits excessive motility and hypertonus of the Gl tract in irritable colon syndrome, mild dysentery, diverticulitis, pylorospasm, and cardiospasm. Transdermal patch Prevention of nausea and vomiting associated with motion sickness and recovery from anesthesia and surgery in adults. 

The anticholinergic agent scopolamine is available as a patch formulation. Its slow release causes a duration of action of 3 days. It is highly effective for motion sickness. 

Scopolamine Unknown mechanism in CNS Reduces vertigo, postoperative nausea Prevention of motion sickness and postoperative nausea and vomiting Transdermal patch used for motion sickness IM injection for postoperative use Toxicity Tachycardia, blurred vision, xerostomia, delirium Interactions With other antimuscarinics... 

Hyoscine (scopolamine), a prototypic muscarinic receptor antagonist, is one of the best agents for the prevention of motion sickness. However, it has a very high incidence of anticholinergic effects when given orally or parenterally. It is better tolerated as a transdermal patch. Superiority to dimenhydrinate has not been proved. 

The most popular use of scopolamine today is for the prevention of motion sickness via the Transderm-Scop patch. This device delivers about 0.5 mg of the drug over a three day period. Scopolamine and other drugs in this class can accumulate in significant quantities in the blood and some can cause CNS effects such as drowsiness, dry mouth and blurry vision. In rare cases amnesia and even psychosis can occur. The sedation and dry mouth are useful effects in that some of the compounds are used as tranquilizers and to dry up the mouth prior to anesthesia. 

Motion Sickness. Antimuscarinics (scopolamine in particular) are frequently used in the treatment of motion sickness.22 Scopolamine appears to block cholinergic transmission from areas of the brain and brainstem that mediate motion-related nausea and vomiting (i.e., the vestibular system and reticular formation).8 These drugs are often administered trans-dermally via small patches that adhere to the skin.18... 

Scopolamine was the first drug to be marketed as a transdermal delivery system (Transderm-Scop) to alleviate the discomfort of motion sickness. After oral administration, scopolamine has a short duration of action because of a high first-pass effect. In addition, several side-effects are associated with the peak plasma levels obtained. Transderm-Scop is a reservoir system that incorporates two types of release mechanims a rapid, short-term release of drag from the adhesive layer, superimposed on an essentially zero-order input profile metered by the microporous membrane separating the reservoir from the skin surface. The scopolamine patch is able to maintain plasma levels in the therapeutic window for extended periods of time, delivering 0.5 mg over 3 days with few of the side-effects associated with (for example) oral administration. 

CNS damping effects. Scopolamine is effective in the prophylaxis ofkinetosis (motion sickness, sea sickness, see p.342) it is mostly applied by a transdermal patch. Scopolamine (pJCa = 7.2) penetrates the blood-brain barrier faster than does atropine (p/Ca = 9), because at physiological pH a larger proportion is present in the neutral, membrane-permeant form. 

In 1978 Tranderm Scop was the first transdermal patch to receive FDA approval. Scopolamine, the active ingredient, is a belladonna alkaloid that is frequently used to treat motion sickness and nausea resulting from anesthetics and analgesics. Transderm Scop is a membrane-moderated patch that has a three-day life span. It has a circular shape with an area (2.5 cm2) approximately the size of a quarter [26]. 

Scopolamine is available as a transdermal drug delivery system fisr prevention of motion sickness. When placed behind the ear the system delivers 0.5 mg of scopolamine for 3 days. Mydriasis and blurred vision can occur if scopolamine from the patch comes in contact with the eyes. 

Scopolamine can cause side effects of dry mouth, drowsiness, tachycardia, central nervous system (CNS) disturbances, and amnesia if plasma concentrations exceed the levels required to alleviate motion sickness (Fig. 10). The application of scopolamine to the posterior auricular areas (the most permeable anatomical site) via a microporous patch permits constant delivery of 0.5 mg over 3 days to prevent motion sickness and avoid side effects. 

The popular Transdermal Scop patches are widely used by travelers who experience motion sickness, and contain 1.5 mg of scopolamine solubilized to approximately 100 mg/ml in mineral oil, and deliver 1.0 mg over three days. Catapres -TTS patches contain 2.5-7.5 mg of clonidine solubilized in mineral oil, and deliver 0.1-0.3 mg/day for seven days. Vivelle-DOT patches contain 0.39-1.6 mg of estradiol solubilized in... 

A transdermal delivery system has been developed for prevention of motion sickness and vomiting, using an adhesive patch for postauricular application the drug is released at a uniform rate for 72 hours. The adverse effects of this formulation are qualitatively typical of those reported for the oral and parenteral formulations of hyoscine and its congeners, although comparative studies suggest that the incidence is reduced with transdermal administration. Nevertheless, adverse effects involving the central nervous system, vision, bladder, and skin have been described, as have withdrawal symptoms after the patch is removed. 

Anesthesiologists appreciate the fact that individuals who experience motion sickness are also at risk of having postoperative nausea and vomiting that may persist for days after surgery. Application of a scopolamine transdermal patch behind the ear for 3 days beyond surgery may serve as a useful adjunct to antiemetic therapy and eradicate this problem (11). 

Skin patches are adhesive patches which contain a reservoir of the drug to be administered. The drug slowly passes from the patch through the skin and into the bloodstream. They are commonly used in hormone replacement therapy, nicotine replacement therapy, pain relief, relief of symptoms of angina, motion sickness, birth control and in the treatment of attention deficit hyperactivity disorder (ADHD). 

As shown in Table 4, sophisticated adhesive patches for transdermal delivery of scopolamine (motion sickness), nitroglycerine (anginal symptoms), clonidine (regulation... 

Transderm Scop (scopolamine) 2-day patch for prevention of nausea and vomiting associated with motion sickness. 

The most commonly used muscarinic receptor antagonist is scopolamine (hyoscine), which usually is administered as the free base in the form of a transdermal patch (transdee(M-scop). Its principal utility is in the prevention and treatment of motion sickness, although it also has some activity in postoperative nausea and vomiting. In general, anticholinergic agents have no role in chemotherapy-induced nausea. 

CNS Scopolamine is standard therapy for motion sickness this drug is one of the most effective agents available for this condition. A transdermal patch formulation is available. Benztropine, biperiden. and trihexyphenidyl are representative of several antimuscarinic agents used in parkinsonism. Although not as effective as levodopa (see Chapter 28), these agents may be useful as adjuncts or when patients become unresponsive to levodopa. Benztropine is sometimes used parenterally to treat acute dystonias caused by antipsychotic medications. 

Atropine is very well absorbed. Scopolamine has a relatively long durtition of fiction, especially when used as an anti-motion sickness transdemial patch. Ipratropium is quaternary and poorly absorbed from the airwciys. Benztropine is tertiary, lipid-soluble, and penetrates into the CNS well. Only (C) is correct. 

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