ACTUAL INFORMATION

Anaprilin (propranolol) is a non-selective β-adrenergic receptor blocker. Its membrane-stabilizing properties have been reported, but the drug does not have internal sympathomimetic activity.

Application

Anaprilin is used as propranolol hydrochloride in the treatment of arterial hypertension, pheochromocytoma, angina pectoris, myocardial infarction and cardiac arrhythmia. It is also used to control hypertrophic cardiomyopathy. The drug is prescribed to control the symptoms of sympathetic hyperactivity, hyperthyroidism, anxiety disorders and tremors. Other indications include the prevention of migraine, gastrointestinal bleeding in patients with portal hypertension.

Dosing

With arterial hypertension, it is administered in initial doses of 40–80 mg 2 times a day, increasing the dose to the usual range of 160–320 mg per day; some patients may require a dose of up to 640 mg per day. Anaprilin is not suitable for emergency treatment of hypertension; should not be administered intravenously with arterial hypertension. With pheochromocytoma, patients referred for surgical treatment can receive 60 mg per day 3 days before surgery, always in combination with an alpha-adrenergic receptor blocker. If the tumor is inoperable, long-term treatment may be prescribed with a daily dose of 30 mg. With angina pectoris, the initial dose of propranolol hydrochloride is 40 mg, they are administered 2-3 times a day, increase as necessary to the usual range of 120-240 mg per day. Some patients may require up to 320 mg per day. Anaprilin is prescribed within 5-21 days after myocardial infarction in doses of 40 mg, administered 4 times a day for 2-3 days, and then 80 mg 2 times a day. Another dosage regimen is to take 180–240 mg per day (divided into equal doses). Anaprilin can be prescribed in doses of 30-160 mg per day, divided into equal doses with long-term treatment of cardiac arrhythmias. For emergency treatment of cardiac arrhythmias, propranolol hydrochloride can be administered slowly as an intravenous injection for 1 min, at a dose of 1 mg, repeating if necessary every 2 min, until a maximum dose of 10 mg is administered to the patient (conscious) and 5 mg for the patient under anesthesia. Patients receiving an iv drug should be carefully monitored. With hypertrophic cardiomyopathy, the usual dose of propranolol hydrochloride is 10–40 mg 3-4 times a day. The dose for anxiety disorders is 40 mg per day; it can be increased to 40 mg 2-3 times a day. Essential tremor can be treated with 40 mg of the drug 2-3 r / day; the dose may be increased at weekly intervals to 160 mg per day, although doses up to 320 mg per day may be required. An initial dose of 40 mg 2-3 times a day is used to prevent migraines; the dose may be increased at weekly intervals to 160 mg per day. Some patients were prescribed a dose of 240 mg daily. In case of portal hypertension Anaprilin should be prescribed in initial doses of 40 mg 2 times a day; the dose can be increased to 160 mg 2 times a day. Children Propranolol hydrochloride is used both orally and intravenously in children, although it is not licensed for all indications. Suggested doses for arterial hypertension: - newborns: 250 mcg / kg orally 3 times a day, if necessary, increase to a maximum of 2 mg / kg 3 times a day; - 1 month - 12 years: from 0.25 to 1 mg / kg orally 3 times a day, increases as necessary to a maximum of 5 mg / kg per day, divided into equal doses; - 12 years or more: dose for adults. For the treatment of arrhythmias, pheochromocytoma and hyperthyroidism: - newborns: 250-500 mcg / kg orally 3 times a day. Alternatively: 20-50 mcg / kg can be administered intravenously 3-4 times a day, administered slowly, constantly monitor the patient's condition; - 1 month - 18 years: 250–500 mcg / kg orally 3-4 times a day, adjusted for a maximum of 1 mg / kg 4 times a day, or a total daily dose of 160 mg. Alternatively: 25-50 mcg / kg can be administered intravenously 3-4 times a day, slowly administered with appropriate control. For migraine prophylaxis: - children under 12 years old: 10–20 mg orally 2-3 times a day; - over 12 years old: dose for adults. Propranolol is soluble in water and alcohol, slightly soluble in chloroform, and practically insoluble in ether.

Pharmacokinetics

Anaprilin is almost completely absorbed from the gastrointestinal tract; however, the achieved plasma concentrations are very different in different people. There is no difference in the rate of absorption of the two propranolol isomers. Propranolol is detected in blood plasma within 30 minutes, and a peak in its concentration is reached 60–90 minutes after ingestion. Propranolol hydrochloride is slowly absorbed after taking the drug in the form of prolonged-action capsules and reaches its peak concentration in the blood 6 hours after administration. The drug is metabolized during the first passage through the liver. Anaprilin is widely accumulated in body tissues, including the lungs, liver, kidneys and heart. It easily penetrates the BBB, the placenta, into breast milk. More than 90% bound to plasma proteins. An increase in the plasma protein binding of the drug increases its metabolism and decreases the volume of distribution, which leads to a shorter T 1/2 . The reported T 1/2 varies greatly in different studies. After iv 10 mg of propranolol hydrochloride at a rate of 1.03 mg / min in one study, plasma concentration decreased over 2 phases. T 1/2 during the initial phase was 10 minutes, and during the final phase was 2.3 hours. The results of another study show that the T 1/2 (L) -enantiomer is 50% longer than the (D) -enantiomer. When the usual therapeutic dose of propranolol is administered continuously, T 1/2 fluctuates between 3.4-6 hours. Single dose studies have generally shown a shorter T 1/2 - 2 –3 h. T 1/2 of propranolol may decrease in patients with reduced renal function. However, there is insufficient evidence to change the maintenance dose for patients with impaired renal function. During initial oral therapy, an active metabolite of 4-hydroxypropranolol is formed. This compound has approximately the same activity as propranolol and can be contained in blood plasma in an amount approximately equal to that of the original substance. This metabolite is more rapidly excreted from blood plasma than propranolol, and is practically absent in it 6 hours after ingestion. Anaprilin is almost completely metabolized in the liver. Only 1–4% of an oral or intravenous dose appears in the feces as unchanged drug and metabolites. Chronic renal failure may be associated with a decrease in drug metabolism in relation to a decrease in the activity of the hepatic enzyme system. Anaprilin , apparently, does not significantly undergo hemodialysis. Reduced clearance and an increase in T 1/2 have been reported in geriatric patients compared to younger patients (Al-Majed A.A. et al., 2017).

Research

Consider some interesting research. Hemangiomas are the most common benign vascular tumors in infants. Although most infantile hemangiomas (IG) have the ability to spontaneously disappear after tumor involution, medical intervention is required in the IG subgroup when complications develop that lead to ulceration, bleeding, or aesthetic deformation. The main treatment for this subgroup is pharmacological intervention, and propranolol has become the first-line drug for complex hemangiomas. The study evaluated the efficacy of propranolol in relation to IG proliferation in a clinical cohort, including 578 patients. A total of 578 patients with IG who were treated with oral propranolol from January 2010 to December 2012 were retrospectively reviewed. Responses to propranolol treatment were classified as: excellent, good, poor, or there was no response to therapy. Based on the response to propranolol treatment (1 time per day at a dose of 1.0 mg / kg for patients younger than 2 months; 2 times a day in a daily total dose of 2 mg / kg for patients older than 2 months), additional pharmacotherapy or surgery was used for patients with IG for a satisfactory clinical result. 560 patients (96.9%) of the total number with IG in the study responded to oral treatment with propranolol, and the frequency of responses varied significantly for patients of different ages, with the youngest patients having the highest level of response. The average treatment time was 6 months (3-12 months). For example, the response rate to propranolol was 98.1% in patients younger than 2 months compared with 93.3% in patients older than 2 months but younger than 8 months, and 73.7% in patients older than 8 months. 131 patients in whom incompletely involutive hemangiomas were detected were additionally treated with timolol maleate or a pulsed dye laser. 117 (89.3%) of 131 patients showed a positive response. There were no life-threatening complications after the use of propranolol. Nevertheless, minor side effects were observed, including 10 (1.73%) cases of sleep disturbance, 7 (1.21%) cases of diarrhea, and 5 (0.86%) bronchospasm. IG requires early intervention. During the involution phase, the dose of propranolol may be reduced to minimize side effects until therapy is discontinued. For patients with telangiectasia and chromatosis after treatment with propranolol, the administration of a 0.5% solution of timolol maleate or a pulsed dye laser is an effective therapeutic approach for complete involution (Zhang L. et al., 2017). Although Anaprilin is still the first choice for migraine prophylaxis, its optimal dose is still unknown. The main goal of one of the studies is to clarify this point. 53 patients suffering from serious migraine attacks received propranolol in low doses, up to 1 mg / kg body weight daily, for 1 month. If the patient gave a positive response to therapy, then the treatment remained unchanged for another 2 months. If there was no response to therapy, the dose of propranolol gradually increased until a response was received. 39 (73.5%) patients responded to low doses, and 7 out of 17 patients whose dose was increased due to a poor or absent response showed improvement. 5 patients did not complete the study due to severe side effects, which intensified with increasing dose. Tolerance was not seen. In support of the known benefits of the drug in the prevention of migraine, the results show that low doses are effective in combating serious migraine attacks in many patients. Less than a third of patients require higher doses to control migraine attacks (Pascual J. et al., 1989). Factors affecting the response of essential tremor to prolonged administration of propranolol (120 mg daily for 2 weeks and then 240 mg daily for another 2 weeks) were studied in a double-blind, cross-placebo-controlled study in 16 patients. Hand tremor was assessed using accelerometers with autonomous computer analysis. It was found that the drug is superior to placebo only at higher doses (240 mg per day). At this dosage, the median decrease in tremor amplitude (compared to the control value) was 45%. The response to the drug (expressed as a percentage change in the amplitude of the tremor) positively correlated with the control amplitude and negatively (but more weakly) with the frequency of the control peak of tremor. In patients with hand tremor greater than 6 × 10 -3 cm, arm displacement decreased by 65% ​​compared to only 17% in patients whose tremor amplitude was below this limit. There was no statistically significant relationship between the percentage change in tremor amplitude and the duration of the disorder and the age of the patients. The results demonstrated that propranolol therapy is not indicated for patients with a small tremor amplitude unless their tremor is greatly exacerbated under conditions of excessive release of adrenergic substances (Calzetti S. et al., 1983). In a double-blind, controlled study, it was found that propranolol at a dose of 120 mg per day is safe and effective in treating 28 patients with chronic neurosis, chronic anxiety who were given this diagnosis, and they were selected in accordance with strict specific criteria. It was found that a reduced dose of propranolol of 40 mg per day is ineffective. The analysis used both one-dimensional and multi-dimensional nonparametric statistics. Problems such as the pathogenetic mechanisms of the occurrence of anxiety symptoms, the mode of action of beta-adrenoreceptor blockers and their place in the treatment of anxiety states, the optimal dose, monitoring the plasma level of the drug, and duration of use were discussed (Tanna V.T. et al., 1977).

Внимание: Эта статья опубликована исключительно в ознакомительных целях. Информация не является медицинской рекомендацией и не побуждает к каким-либо действиям. Перед применением любых препаратов или методов лечения обязательно проконсультируйтесь с врачом.

Отказ от ответственности: Все материалы на этом сайте защищены авторскими правами. Перепечатка и использование информации разрешены только с указанием источника. Вся информация носит информационный характер и не является заменой консультации с профессионалами в области медицины. Использование материалов допускается только с соблюдением возрастных ограничений, если таковые предусмотрены.