digoxin and pentaacetylgitoxin

Topics: Acetyldigoxins; Digitalis Glycosides; Digitoxin; Digoxin; Drug Utilization; Germany, East; Humans; Lanatosides

Color discrimination ability of 100 in-patients suffering from congestive heart failure and treated with digitoxin (D), pengitoxin (P), or digoxin (Dg) was determined with the Farnsworth-Munsell 100 Hue test (FM 100) and compared with the color discrimination of 72 in-patients who were not treated with digitalis glycosides (control group C). Parallel to the performance of the FM 100, the glycoside plasma level was measured by radioimmunoassay. The total error score (TES) of the FM 100 was correlated with the glycoside plasma level and the patient's age. In the C as well as in the D or P groups up to 172 errors and in the Dg group up to 586 errors were observed. With the exception of Dg, no differences were observed between the regression lines indicating an age-dependent increase in TES even under D or P treatment. In contrast to the two glycosides, Dg enhances the TES in therapeutically relevant plasma concentrations. The differences between the glycosides are due to differences in their volume of distribution and their plasma protein binding.

Topics: Acetyldigoxins; Adolescent; Adult; Aged; Aged, 80 and over; Color Perception; Digitoxin; Digoxin; Discrimination, Psychological; Female; Heart Failure; Humans; Male; Middle Aged

In a therapeutic study, 120 inpatients suffering from congestive heart failure were treated with a daily maintenance dose of 0.3 mg pengitoxin (penta-acetyl-gitoxin) over several weeks or months. The plasma level and the glycoside concentration in urine were measured by radioimmunoassay. The therapeutic effects were evaluated considering clinical signs and criteria following the functional capacity according to the New York Heart Association (NYHA). In 27 patients both plasma and urine concentration were measured during 2 weeks after the beginning of the pengitoxin therapy. On the 3rd day of the pengitoxin dosage schedule, a mean plasma level of 18.1 ng.ml-1 (SD 5.1 ng.ml-1) was measured. During this day 26.6% of the daily administered glycoside dose was excreted in urine. In 26 of the 120 patients the mean steady state plasma level was between 7.6 and 22.5 ng.ml-1. A maximum of frequency was found in the 17.6 to 22.5 ng-subclass. In 118 patients the mean urinary excretion of 16-acetyl-gitoxin reached 24.7% (SD 11.8%) of the administered dose. The creatinine clearance and the 16-acetyl-gitoxin plasma level did not correlate, while between the renal clearance values of creatinine and the glycoside a correlation was found, however, it was of no significance for dosage schedules in patients with impaired renal function. After treatment, the NYHA classes III and II were reached in 57 patients; in 3 patients suffering from renal diseases, the NYHA class I remained unchanged. In 90 patients the clinical signs improved and in 27 patients the clinical situation remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Acetyldigoxins; Adolescent; Adult; Aged; Aged, 80 and over; Biological Availability; Digoxin; Electrocardiography; Female; Glycosides; Heart Failure; Humans; Male; Middle Aged

The systolic time intervals (STI) corrected for changes in the heart rate, electromechanical systole (QS2c) and left ventricular ejection time (LVETc), and the ECG-derived PQ-time and QT-interval were measured in five female and four male healthy subjects. Each volunteer took 0.15, 0.30, 0.45, 0.60, 0.75 or 0.90 mg pengitoxin over six days, with a glycoside-free interval of two or three weeks between two doses. The glycoside plasma level was measured radioimmunologically. Linear correlations were found between the shortening of QS2, LVET, and QT (delta QS2c, delta LVETc, delta QTc) and the plasma level of 16-acetyl-gitoxin. The PQ-time showed a flat dose-dependent increase. The shortening of STI observed after therapeutic and subtoxic doses of pengitoxin was in accordance with that after intake of digitoxin and digoxin in corresponding doses. The efficacy of pengitoxin estimated by shortening of STI justifies the administration of daily maintenance doses between 0.30 and 0.45 mg.

Topics: Acetyldigoxins; Adult; Digoxin; Dose-Response Relationship, Drug; Electrocardiography; Female; Heart Rate; Humans; Male; Radioimmunoassay

In ten patients suffering from moderate to severe disturbances of liver function (hepatic cirrhosis, carcinomatous metastases of the liver) the elimination of 16-acetyl-gitoxin from plasma was measured after a single oral dose of 1.2 mg pengitoxin. In 9 of 10 patients the mean half-life amounted to 67.3 h (SD 14.2 h). In one patient with carcinomatous infiltration of the liver and concomitant cirrhosis, the half-life was prolonged to 165.3 h. The results point to an unchanged elimination of 16-acetyl-gitoxin in patients suffering from liver cirrhosis.

Topics: Acetyldigoxins; Adult; Aged; Biotransformation; Digoxin; Half-Life; Humans; Liver Diseases; Middle Aged

In six volunteers the pharmacokinetics of 16-acetyl-gitoxin (16AG, 0.5 mg) administered intravenously (A1) and as an oral solution (A2) and of pengitoxin (PAG, 0.6 mg) administered intravenously (A3) was evaluated. In six volunteers the bioavailability of 16AG from two PAG tablet formulations (1.2 mg) (B2, B3) was measured by comparison with the absorption after administration of a pengitoxin solution (1.2 mg) (B1). In both studies the test was performed using a crossover design. After a single i.v. injection of equimolar doses, 16AG and PAG showed similar mean kinetic parameters: t1/2 = 51.6 hr (16AG) and 60.8 hr (PAG), CL = 11.7 ml min-1 (16AG) and 12.7 ml min-1 (PAG), CLR = 4.1 ml min-1 (16AG) and 4.2 ml min-1 (PAG). The 16AG was absorbed from solution with a mean half-life of 0.2 hr to an extent of 98.6%. The mean urinary excretion/Ae (0,4)/of 16AG amounted to 24.6% (A1), 20.8% (A2) and 28.1% (A3). On the basis of AUC values, the mean bioavailability of PAG from either tablet formulation amounted to 79.6% (B2) and 89.6% (B3). The pharmacokinetic parameters of 16AG (PAG) are closer to those of digitoxin than those of digoxin. In general, 16AG is characterized as a digitoxin with a digoxin-like elimination half-life.

Topics: Acetyldigoxins; Administration, Oral; Adult; Biological Availability; Digitoxin; Digoxin; Female; Humans; Injections, Intravenous; Kinetics; Male; Tablets

The pharmacokinetics of pengitoxin has been studied in 28 healthy subjects after intravenous and oral administration. The mean plasma concentration 24 h after 0.5 mg i.v. was 5.2 ng X ml-1. Following an open two-compartment model a mean elimination half-life of 60.5 h (24.9 to 103.5 h) and a mean volume of distribution (Vdarea) of 66.91 (31.8 to 109.61) were calculated. Absorption calculated by comparison of the AUC0-infinity-values amounted to 99%. Within 4 days, 16.7% (11.7 to 21.1%) or 27.8% (18.4 to 33.7%) (0.5 mg i.v. or 1.2 mg p.o.) was excreted in urine. After pengitoxin 0.5 mg i.v. total body clearance and renal clearance were 13.3 ml X min-1 (7.0 to 18.6 ml X min-1) and 3.0 ml X min-1 (1.9 to 3.9 ml X min-1) respectively. The elimination half-life of pengitoxin is longer than that of digoxin and distinctly shorter than that of digitoxin, whilst its distribution volume and clearance are closer to those of digitoxin than of digoxin.

Topics: Acetyldigoxins; Adult; Digoxin; Female; Humans; Kinetics; Male; Radioimmunoassay