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药品简介 Active Ingredients: Ropinirole and its metabolites have negligible in vitro affinity for dopamine D1, 5-HT1, 5-HT2, benzodiazepine, GABA, muscarinic, alpha1-, alpha2-, and beta-adrenoreceptors. Parkinson's Disease: The precise mechanism of action of REQUIP as a treatment for Parkinson's disease is unknown, although it is believed to be due to stimulation of postsynaptic dopamine D2-type receptors within the caudate-putamen in the brain. This conclusion is supported by studies that show that ropinirole improves motor function in various animal models of Parkinson's disease. In particular, ropinirole attenuates the motor deficits induced by lesioning the ascending nigrostriatal dopaminergic pathway with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in primates. The relevance of D3 receptor binding in Parkinson's disease is unknown. Restless Legs Syndrome (RLS): The precise mechanism of action of REQUIP as a treatment for Restless Legs Syndrome (also known as Ekbom Syndrome) is unknown. Although the pathophysiology of RLS is largely unknown, neuropharmacological evidence suggests primary dopaminergic system involvement. Positron emission tomographic (PET) studies suggest that a mild striatal presynaptic dopaminergic dysfunction may be involved in the pathogenesis of RLS. Clinical Pharmacology Studies: In healthy normotensive subjects, single oral doses of REQUIP in the range 0.01 to 2.5 mg had little or no effect on supine blood pressure and pulse rates. Upon standing, REQUIP caused decreases in systolic and diastolic blood pressure at doses above 0.25 mg. In some subjects, these changes were associated with the emergence of orthostatic symptoms, bradycardia, and, in one case, transient sinus arrest with syncope. With repeat dosing and slow titration up to 4 mg once daily in healthy volunteers, postural hypotension or hypotension-related adverse events were noted in 13% of subjects on REQUIP and none of the subjects on placebo. The mechanism of postural hypotension induced by REQUIP is presumed to be due to a D2-mediated blunting of the noradrenergic response to standing and subsequent decrease in peripheral vascular resistance. Nausea is a common concomitant of orthostatic signs and symptoms. At oral doses as low as 0.2 mg, REQUIP suppressed serum prolactin concentrations in healthy male volunteers. REQUIP had no dose-related effect on ECG wave form and rhythm in young, healthy, male volunteers in the range of 0.01 to 2.5 mg. REQUIP had no dose- or exposure-related effect on mean QT intervals in healthy male and female volunteers titrated to doses up to 4 mg/day. The effect of REQUIP on QT intervals at higher exposures achieved either due to drug interactions or at doses used in Parkinson's disease has not been systematically evaluated. What is it used for?: (Indications:) Requip can be taken with or without levodopa (usually prescribed as Sinemet), another drug used to treat the symptoms of Parkinson's disease. Contraindications and cautions: At the start of Requip therapy and whenever the dose is increased, you face a slightly increased risk of a fainting spell or other symptoms of low blood pressure such as dizziness, nausea, sweating, and light-headedness, particularly when you get up suddenly after sitting or reclining for a prolonged period. To avoid such symptoms, be careful to stand up slowly. A few patients--especially older ones--also develop hallucinations. Let your doctor know if this occurs. You may have to stop Requip therapy. Use Requip with caution if you have heart disease. There is also a slight chance of developing respiratory difficulties or problems with your eyesight. If you find it hard to breathe, have any swelling, or develop problems with your vision, alert your doctor at once. If you are taking Sinemet with Requip, you may experience jerking muscle movements. Tell your doctor. He will need to decrease your dose of Sinemet. With other Parkinson's medications, a sudden dose reduction has been known to cause high fever, muscle stiffness, and loss of consciousness. Although this has not happened with Requip, be alert for such problems and contact your doctor immediately if they occur. Requip may cause drowsiness, and some people have reported falling asleep without warning during their daily activities. Do not drive a car or operate machinery until you know how the drug affects you. If you find that Requip makes you sleepy or that you're suddenly falling asleep in the middle of routine activities, tell your doctor; he will probably discontinue the drug. Requip may also cause darkening of your skin and eye color. Tell your doctor if you notice any change. Although the effects of Requip during pregnancy have not been adequately studied in humans, birth defects have occurred in animals. If you are pregnant or plan to become pregnant, inform your doctor immediately. Requip may inhibit production of breast milk. There is also a possibility that it will appear in breast milk and affect the nursing infant. If Requip is essential to your health, your doctor may advise you to discontinue breastfeeding. Side effects: • More common side effects may include: Interactions:
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