Action And Clinical Pharmacology: The pharmacological properties of ergotamine are extremely complex; some of its actions are unrelated to each other, and even mutually antagonistic. Ergotamine: Has partial agonist and/or antagonist activity against tryptaminergic, dopaminergic and alpha adrenergic receptors depending upon their site; is a highly active uterine stimulant; it causes constriction of peripheral and cranial blood vessels and produces depression of central vasomotor centres. The pain of a migraine attack is believed to be due to greatly increased amplitude of pulsations in the cranial arteries, especially the meningeal branches of the external carotid artery. Ergotamine reduces extracranial blood flow, causes a decline in the amplitude of pulsation in the cranial arteries, and decreases hyperperfusion in the territory of the basilar artery. It does not reduce cerebral hemispheric blood flow. Long-term usage has established the fact that ergotamine tartrate is effective in controlling up to 70% of acute migraine attacks. Ergotamine produces constriction of both arteries and veins. In doses used in the treatment of vascular headaches, ergotamine usually produces only small increases in blood pressure but it does increase peripheral resistance and decreased blood flow in various organs. Small doses of the drug increase the force and frequency of uterine contraction; larger doses also increase the resting tone of the uterine muscle. The gravid uterus is particularly sensitive to these effects of ergotamine. Although specific teratogenic effects attributable to ergotamine have not been found, the fetus may suffer if ergotamine is given during pregnancy. Retarded fetal growth and an increased incidence of intrauterine death and resorption have been seen in animals. These are thought to result from ergotamine induced increases in uterine motility and vasoconstriction in the placental vascular bed.
Indications And Clinical Uses: Acute migraine and related types of vascular headache.
Contra-Indications: In peripheral vascular disease (thromboangiitis obliterans, luetic arteritis, severe arteriosclerosis, thrombophlebitis, Raynaud’s disease), coronary heart disease, hypertension, angina pectoris, cardiac arrhythmias, heart blocks, impaired hepatic or renal function, severe pruritus, sepsis, peptic ulcer, infectious states, malnutrition. It is also contraindicated in patients who are hypersensitive to any of its components.
Pregnancy and Lactation: Ergotamine is contraindicated in women who are pregnant, who may become pregnant or who are breast-feeding.
Manufacturers’ Warnings In Clinical States: Undesirable reactions to ergotamine may best be prevented by avoidance of excessive dosage and careful supervision of the patient so that they will not use the drug in larger dosage, more frequently, or for a longer time than prescribed by the physician.
Because of the possible cumulative effects of ergotamine tartrate, the dosage must not exceed 3 tablets in any 24 hour period; and, not more than 5 tablets in 1 week. Patients should be cautioned to use the minimal effective dose to control their symptoms.
Individual sensitivity to the vascular effects of ergotamine varies considerably and symptoms of arterial insufficiency have been reported after as little as 2 mg taken orally. This is a rare occurrence, but if such symptoms develop the use of ergotamine should be discontinued. Failure to recognise the early symptoms of arterial insufficiency has on rare occasions led to irreversible vascular change with therapeutic doses of ergotamine.
Precautions: Ergotamine is not recommended as a prophylactic agent in migraine. Prolonged use should be avoided because of risk of potential serious adverse effects.
Patients who have prolonged specific neurological phenomena (visual, sensory, motor) require great caution and careful follow-up.
Like all drugs, ergotamine should be kept out of reach of children.
Children: The safety and efficacy of ergotamine in children has not been established. It is not recommended for use in children.
Pregnancy: Ergotamine may cause fetal harm when administered to a pregnant woman by virtue of its powerful uterine stimulant actions. It is contraindicated in women who are, or may become pregnant.
Lactation: Ergotamine is secreted into human milk. It can reach the breast-fed infant and exert pharmacological effects, therefore ergotamine is contraindicated in nursing women.
Drug Dependence: Patients who take ergotamine for extended periods of time may become dependent upon it and require progressively increasing doses for relief of vascular headaches or to prevent the increasing dysphoric effects which may follow withdrawal of the drug.
Drug Interactions: The concomitant use of ergotamine alkaloids and beta-blocking agents increases the risks of peripheral vasoconstriction. Among patients treated concomitantly with ergotamine and propranolol a few cases of vasospastic reactions have been reported.
There is some evidence that the concomitant use of triacetyloleandomycin (TAO/Troleandomycin), erythromycin or josamycin and ergotamine can result in an elevated concentration of ergotamine in the plasma, thereby increasing the risk of adverse effects.
Adverse Reactions: The following adverse reactions were reported after therapeutic doses of ergotamine tartrate: nausea, vomiting, diarrhea, polydipsia, tingling of the hands and feet, muscle pains and cramps, thrombophlebitis, vascular spasm, transient tachycardia or bradycardia, rare cases of gangrene, sleepiness, exhaustion, ECG changes, precordial pain, angina and myocardial infarction.
Symptoms And Treatment Of Overdose: Symptoms: Some cases of ergotamine poisoning have been reported in patients who have taken less than 5 mg of the drug. Usually, however, toxicity is seen in doses of ergotamine tartrate in excess of about 15 mg in 24 hours or 40 mg in a few days.
The symptoms of ergotamine poisoning include cold, pale and numb extremities, muscle pain both with and without activity, decreased or even obliterated peripheral pulses and gangrene of the fingers and toes. Other symptoms of ergotism may occur including anginal pain, tachycardia, bradycardia, hypotension or hypertension, headache, nausea, vomiting, diarrhea, itching, formication, anal burning, weakness, miosis, confusion, depression, drowsiness and possible unconsciousness, increase in muscle tone with pain and trismus, and rarely convulsions and hemiplegia. Respiratory depression can also occur.
Overdosage is particularly likely to occur in patients with sepsis or impaired renal or hepatic function. Patients with peripheral vascular disease are specially at risk of developing peripheral ischemia following treatment with ergotamine.
Treatment: Includes withdrawal and elimination of the offending drug and symptomatic therapy. 1) Emesis: If the patient is conscious, induce vomiting with syrup of ipecac (15 to 30 mL). 2) Perform gastric lavage followed by the administration of activated charcoal if the pharyngeal and laryngeal reflexes are present and if less than 4 hours have elapsed since ingestion. Do not attempt gastric lavage on an unconscious patient unless cuffed endotracheal intubation has been performed to prevent aspiration and pulmonary complications. 3) Catharsis: Following gastric lavage, a saline cathartic (sodium or magnesium sulfate 30 g in 250 mL of water) may be introduced and left in the stomach. 4) Diuresis: There is no evidence that forced diuresis accelerates elimination of ergotamine.
Maintenance of adequate pulmonary ventilation: Perform pharyngeal and tracheal suction to remove mucous secretions. Judicious administration of oxygen is also indicated. However, oxygen without assisted respiration must be used with caution, as its use in hypoventilation-hypoxia may result in further respiratory depression and hypercapnia. In more critical cases, endotracheal intubation and tracheostomy, with or without assisted respiration, may be necessary.
Correction of hypotension: Hypertension may occur in the early stages of acute intoxication. However, in severe cases this is usually followed by hypotension. 1) Mild to moderate cases: Most cases of hypotension can be managed with simple measures such as placing the patient in the Trendelenburg position, or administering i.v. fluids, e.g., physiological saline. 2) Severe cases: If satisfactory relief of hypotension cannot be achieved using the above measures, vasopressors should be considered.
Control of convulsions: Convulsions are always a possibility in acute ergotamine intoxication, and may be controlled with diazepam.
Treatment of peripheral vasospasm: Marked peripheral vasospasm with coldness and poor or absent pulses in the hands and feet are commonly associated with acute ergotamine poisoning. Warmth, but not heat, and protection must be afforded the ischemic limbs. Vasodilators, such as sodium nitroprusside or tolazoline, may be used with benefit.
General supportive measures for unconscious patients: 1) Good nursing care is of prime importance and should include regular observation and accurate recording of the vital signs and depth of coma, maintenance of the airway, frequent turning and other routine measures usually adopted with unconscious patients. 2) Careful supervision and recording of fluid intake and output is essential. 3) Prophylactic anticoagulant therapy in the patient with evidence of ischemia should be considered.
Dosage And Administration: Adults: Initiate therapy as soon as possible after the first symptoms of the attack are noted, since success is proportional to rapidity of treatment, and lower dosages will be effective. At the first sign of an attack, or to relieve the symptoms of the full blown attack, place 1 tablet beneath the tongue. An additional tablet may be taken at half-hourly intervals thereafter, if necessary; but dosage must not exceed 6 mg (3 tablets) in any 24-hour period. Limit dosage to not more than 10 mg (5 tablets) in any 1 week.
Availability And Storage: Each light green sublingual tablet contains: ergotamine tartrate USP 2 mg. Nonmedicinal ingredients: cornstarch, D&C Yellow No. 10, FD&C Blue No. 1, lactose, magnesium stearate, peppermint oil and sodium cyclamate. Tartrazine-free. Packages of 12, sealed in unit dose foil strip. Protect from light and heat. (Shown in Product Recognition Section)
ERGOMAR® Rhône-Poulenc Rorer Ergotamine Tartrate Migraine Therapy
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