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reserpine / Demi-RegrotonTM , HydropresTM ,RegrotonTM ,SalutensinTM , Ser-AP-EsTM ,SerpasilTM ,DiupresTM
BLOOD PRESSURE:
HIGH RISK
Description: Reserpine, an antihypertensive, is a rauwolfia alkaloid derived from the root of Rauwolfia serpentina, a shrub native to India. Rauwolfia alkaloids were first used for the treatment of hypertension and psychoses in India during the 1930s but were not used in Western medicine until the 1950s. Reserpine was approved by the FDA in 1953. Reserpine was the first drug found to interfere with the human sympathetic nervous system, and it initiated the effective pharmacotherapeutic control of hypertension. Recently, the use of reserpine as an antihypertensive agent has diminished due its adverse CNS effects and the advent of newer antihypertensive drugs that are equally effective and much better tolerated. Use of rauwolfia alkaloids in patients with psychotic disorders has been replaced by treatment with other, more effective agents.
Mechanism of Action: Reserpine depletes stores of serotonin and norepinephrine in the brain, adrenal medulla, and other tissues, and reduces the reuptake of catecholamines by adrenergic nerve terminals. The drug binds tightly to catecholamine storage vesicles in the adrenergic neuron, eventually destroying these vesicles so that the terminals cannot concentrate or store norepinephrine or dopamine. This process also occurs in vesicles that store serotonin (5-hydroxytryptamine). The result of reserpine's effects on biogenic amines is sympathetic dysfunction, with a subsequent decrease in peripheral vascular resistance and a lowering of blood pressure often associated with bradycardia. Cardiac output, renal blood flow, and glomerular filtration rate are also decreased. After reserpine is discontinued, the synthesis of new vesicles can restore sympathetic function, but this can take several weeks.
Reserpine produces a tranquilizing effect by depletion of catecholamines in the brain. Convulsions and extrapyramadal effects have occurred following high doses of reserpine. Respiratory stimulation occurs at small doses and respiratory depression occurs with large doses. Additionally, reserpine-induced adrenergic blockade results in increased parasympathomimetic effects including increased gastric acid secretion, GI hypermotility, and miosis.
Pharmacokinetics: Reserpine is absorbed rapidly from the GI tract following oral administration, but the hypotensive effects usually are not observed for 2-3 weeks. The drug distributes throughout the body tissues and is completely metabolized in the liver to inactive derivatives. Reserpine that is bound to vesicles cannot be removed with dialysis, indicating that the amount of drug bound to vesicles and the amount present in the medium are not in equilibrium. Metabolites of the drug are excreted gradually in the urine and feces; antihypertensive effects can last for weeks following discontinuance of therapy.
CONTRAINDICATIONS/PRECAUTIONS: Reserpine can increase gastric acid secretion and increase gastric motility. Conditions such as peptic ulcer disease and ulcerative colitis may be exacerbated by reserpine. The drug should be used with caution in patients with a history of these diseases. Reserpine also should be used cautiously in patients with a history of cholelithiasis because biliary colic could occur.
Reserpine should be used with caution in patients with cardiac disease such as cardiac arrhythmias or pheochromocytoma. Reserpine has been reported to cause arrhythmias and bradycardia.
Reserpine can cause decreased mental function, and patients should be warned of the hazards of operating heavy machinery or driving an automobile while receiving reserpine. Depression can be aggravated by reserpine therapy, so the drug should be used with caution in patients with a history of major depression. Also, reserpine should be used with caution in patients with Parkinson's disease.
Reserpine is contraindicated in patients receiving electroconvulsive therapy (ECT) because depletion of catecholamines can increase the risk of convulsions. It is recommended that following reserpine therapy, at least 1 week should elapse before electroconvulsive therapy is initiated. Reserpine should not be used in patients with a seizure disorder.
Reserpine should not be used in patients who have renal disease because the hypotensive properties of reserpine can cause kidney function to decrease further. However, dosage adjustment is necessary in patients with renal impairment.
Certain preparations of reserpine (e.g., NaquivalTM , Metatensin #2TM , RaudixinTM 50-and 100-mg, and RauzideTM ) contain tartrazine dye and can cause allergic responses in patients who are hypersensitive to this dye. Although the incidence of tartrazine dye hypersensitivity is low, it can be serious, so caution should be used when administering the drug to patients with tartrazine dye hypersensitivity or to patients with aspirin sensitivity.
This drug is classified as pregnancy risk category D. Although there have been no adequate human studies of the effects of this drug upon the fetus, animal reproduction studies have shown adverse fetal effects. Therefore, in making the decision to administer this drug during pregnancy, the potential risks to the fetus must be weighed against the potential benefits to the mother. In addition, reserpine is excreted into breast milk in significant amounts to cause increased respiratory tract secretions, nasal congestion, cyanosis, and anorexia in breast-feeding infants.
DRUG INTERACTIONS: The concomitant administration of reserpine with diuretics or other antihypertensive agents can result in additive hypotensive effects. In some patients, this interaction may be desirable, but dosages should be adjusted accordingly.
Reserpine, by depleting catecholamines, can increase the hypotensive effects of propranolol or other œ-blockers, including ophthalmic œ-blockers. Patients receiving these drugs should be monitored carefully for bradycardia or hypotension if reserpine is added.
Concomitant administration of reserpine and cardiac glycosides can increase the risk of developing arrhythmias, especially when large doses of reserpine are used. These drugs are often effective when administered together, but the risk of precipitating arrhythmias still remains. Reserpine-induced angina and arrhythmias are more likely to occur during concomitant administration of procainamide, cardiac glycosides, or quinidine.
Administration of reserpine to patients receiving monoamine oxidase inhibitors (MAOIs), such as furazolidone, procarbazine, and selegiline, can cause hypertension and increased excitation. These effects presumably are due to the sudden increases in catecholamine levels. Administration of MAOIs to patients receiving reserpine can potentiate the adverse CNS depressant effects.
Administration of reserpine can potentiate the depressant effects of CNS depressants such as ethanol and barbiturates.
Concomitant administration of reserpine with tricyclic antidepressants has been beneficial in treating depression refractory to antidepressants alone, but in some cases, CNS excitability has been reported. In general, reserpine and tricyclic antidepressants should not be administered together.
Because reserpine can decrease dopamine stores, it can antagonize the effects of levodopa. Dosage adjustments of one or both agents may be required when administering these drugs together.
Nonsteroidal antiinflammatory drugs (NSAIDs) can reduce the antihypertensive effects of reserpine by inhibiting renal prostaglandin synthesis and/or increasing sodium and fluid retention. Patients receiving these agents concomitantly should be monitored closely to ensure that the desired antihypertensive effect is achieved.
Reserpine can antagonize the inhibitory effects of anticholinergic agents on gastric acid secretion.
The use of estrogens can increase fluid retention and increase blood pressure, thereby antagonizing the antihypertensive effects of reserpine.
Concomitant use of reserpine with sympathomimetics, such as cocaine, dobutamine, dopamine, norepinephrine, epinephrine, metaraminol, methoxamine, phenylephrine, phenylpropanolamine, or ephedrine, can potentiate the vasopressor effects of these agents, antagonizing the antihypertensive effects of reserpine. The mechanism of this interaction is believed to involve reserpine-induced inhibition of the uptake of the sympathomimetic drug by adrenergic neurons, possibly resulting in hypertension and cardiac arrhythmias. Because reserpine depletes catecholamine stores, it can also inhibit the actions of indirect-acting amines (amphetamines, phenylpropanolamine, pseudoephedrine, and tyramine) or direct-acting amines (ephedrine and mephentermine).
ADVERSE REACTIONS: Adverse CNS effects, including fatigue, dizziness, and drowsiness or lethargy, can occur during reserpine therapy. Mental depression can potentially be severe and can occur in any patient receiving the drug. Therapy should be discontinued if signs of depression are reported. Reserpine-induced depression can last for several months following discontinuance of the drug.
Edema with fluid retention and dyspnea can occur with reserpine therapy, and eventually can lead to congestive heart failure. These adverse effects can be alleviated by concomitant administration of a diuretic.
Reserpine can cause miosis, which is slight, but can last up to a week after a single dose. Conjunctivitis has been reported secondary to conjunctival blood vessel dilation.
Hypotension, sinus bradycardia, and/or arrhythmias can occur with reserpine therapy; cardiovascular responses are especially unpredictable following IV administration of the drug. Reserpine-induced angina and cardiac arrhythmias are more likely to occur during concomitant administration of procainamide, cardiac glycosides, or quinidine.
Adverse GI symptoms can occur during reserpine use and include nausea/vomiting, abdominal pain, diarrhea, and anorexia. Gastric acid secretion is increased during reserpine therapy, possibly aggravating or reactivating peptic ulcer disease.
Reserpine can cause various types of sexual dysfunction. Libido decrease can be seen in both men and women. Impotence and ejaculation dysfunction including decreased or no ejaculation has been reported. PATIENT INFORMATION: What do reserpine tablets do? RESERPINE is an antihypertensive. It helps lower high blood pressure (hypertension) to normal levels. High blood pressure levels can cause you to have a stroke, get heart failure, or damage your kidneys. Reserpine is not a cure for high blood pressure. Generic reserpine tablets are available.
What should my doctor, dentist, or pharmacist know before I take reserpine?
They need to know if you have any of these conditions:
How should I take this medicine?
Take reserpine tablets by mouth. Follow the directions on the prescription label. Swallow the tablets with a drink of water. If reserpine upsets your stomach you can take it with food or milk. Take your doses at regular intervals. Do not take your medicine more often than directed.
Special precautions for use in children:
This medicine is not for children.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What other medicines can interact with reserpine?
Tell your doctor or pharmacist: about all other medicines you are taking, including non-prescription medicines; if you are a frequent user of drinks with caffeine or alcohol; if you smoke; or if you use illegal drugs. These may affect the way your medicine works. Check before stopping or starting any of your medicines.
What side effects may I notice from taking reserpine?
Serious side effects with reserpine include:
Call your doctor as soon as you can if you get any of these side effects.
Minor side effects with reserpine include:
Let your doctor know about these side effects if they do not go away or if they annoy you.
What do I need to watch for while I take reserpine?
Visit your doctor for regular checks on your progress. Check your heart rate and blood pressure regularly while you are taking reserpine. Ask your doctor what your heart rate should be and when you should contact him or her.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how reserpine affects you. To avoid dizzy or fainting spells, do not stand or sit up quickly, especially if you are an older person. Alcohol can make you more drowsy and dizzy. Avoid alcoholic drinks.
Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water will help.
Where can I keep my medicine?
Keep out of the reach of children in a container that small children cannot open.
Store at room temperature between 15 and 30C (59 and 86F). Protect from light. Keep container tightly closed. Throw away any unused medicine after the expiration date.
The P-I-E-N-O Parkinsn's List Drug Database Index
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