medigoxin and Body-Weight

In 1063 patients (greater than or equal to 60 years, 531 men, 532 women) the plasma concentration during digitalis maintenance therapy (metildigoxin, n = 356, beta-acetyldigoxin, n = 359, and digitoxin, n = 348) was determined and related to sex, age, body weight, serum potassium, renal function and the prescribed daily maintenance dose. Classification of treatment groups according to renal function (Crea less than or equal to 1.3 mg/dl parallel greater than 1.3 mg/dl) did not show any difference of the mean maintenance doses. In multiple linear regression analyses only a weak relationship between plasma digitalis concentration and the studied variables was found, which could be equally attributed to dose, creatinine and serum potassium in the digoxin derivative groups, whereas for digitoxin only body weight had a significant effect on the plasma concentration. During a maintenance dose of 0.07 or 0.1 mg/die which was given to 87% of patients in the digitoxin group, 70% were found to have plasma levels within the therapeutic range.

Topics: Acetyldigoxins; Aged; Body Weight; Digitoxin; Digoxin; Dose-Response Relationship, Drug; Heart Failure; Humans; Kidney Function Tests; Medigoxin

A retrospective study of two groups of patients with a different plasma digoxin level (Group A: digoxin greater than or equal to 2 ng/ml, n = 32, Group B: digoxin less than 2 ng/ml, n = 34; total n = 66) showed a significantly lower creatinine clearance (p less than 0.05) in group A. This group also showed a weak correlation between the digoxin level and the length of observation (R = + 0.31, p less than 0.05, n = 29). Furthermore, a weak correlation between digoxin level and the ratio of average daily dosage to creatinine clearance was found for the total sample (R = + 0.30, p less than 0.05, n = 66). Patients treated for less than 7 days and with a higher digoxin level also had a higher dosage and worse renal function (p = 0.05, p = 0.01, respectively). A weak correlation also existed between the digoxin level and creatinine clearance and body weight for the whole sample (R = -0.29, p less than 0.05; R = -0.29, p less than 0.01, respectively; n = 66). The latter correlation was also found within each group. Apart from renal function, the medication taken and body weight seem to be useful variables in predicting impending elevation of the digoxin level. In this study these variables were found to be better suited for the said purpose than the ECG. These conclusions remain to be confirmed by means of a prospective study.

Topics: Acetyldigoxins; Age Factors; Arrhythmias, Cardiac; Body Weight; Creatinine; Digoxin; Dosage Forms; Dose-Response Relationship, Drug; Drug Administration Schedule; Electrocardiography; Female; Humans; Kidney Function Tests; Male; Medigoxin; Risk