Lanoxin Tablets 250mcg are white, round, biconvex tablets, bisected
and debossed "D025" on the same side and plain on the other side.
Each tablet contains 250mcg (0.250mg) of Digoxin BP.
Lanoxin PG Tablets are blue, round, biconvex tablets, debossed
"D06" on the one side and plain on the other side.
Each tablet contains 62.5mcg (0.0625mg) of Digoxin BP.
Lanoxin is indicated in the management of chronic cardiac failure
where the dominant problem is systolic dysfunction. Its therapeutic
benefit is greatest in those patients with ventricular dilatation.
Lanoxin is specifically indicated where cardiac failure is accompanied
by atrial fibrillation.
Lanoxin is indicated in the management of certain supraventricular
arrhythmias, particularly atrial flutter and fibrillation, where a major
beneficial effect is reduction of the ventricular rate.
DOSAGE AND ADMINISTRATION
The dose of Lanoxin for each patient has to be tailored individually
according to age, lean body weight and renal function.
Suggested doses are intended only as an initial guide.
Adults and children over 10 years
Rapid Oral Loading
750 to 1500 μg (0.75 to 1.5 mg) as a single dose.
Where there is less urgency, or greater risk of toxicity e.g. in the
elderly, the oral loading dose should be given in divided doses
6 hours apart, with approximately half the total dose given as the first
Clinical response should be assessed before giving each additional
dose (see Warnings and Precautions).
Slow Oral Loading
250 to 750 g (0.25 to 0.75 mg) should be given daily for 1 week
followed by an appropriate maintenance dose. A clinical response
should be seen within one week.
NOTE: The choice between slow and rapid oral loading depends on
the clinical state of the patient and the urgency of the condition.
The maintenance dosage should be based upon the percentage of
the peak body stores lost each day through elimination. The following
formula has had wide clinical use:-
Where:- Peak body stores = loading dose
daily loss (in percent) = 14 + creatinine clearance (Ccr)/5
Ccr is creatinine clearance corrected to 70 kg bodyweight or 1.73
m2 body surface area.
If only serum creatinine (Scr) concentrations are available, a Ccr
(corrected to 70 kg bodyweight) may be estimated in men as
NOTE: Where serum creatinine values are obtained in μmol/L, these may be
converted to mg/100 ml (mg%) as follows:-
Where 113.12 is the molecular weight of creatinine. For women, this result
should be multiplied by 0.85.
N.B.: These formulae cannot be used for creatinine clearance in children.
In practice, this will mean that most patients will be maintained on 125 to
750 μg (0.125 to 0.75 mg) digoxin daily; however in those who
show increased sensitivity to the adverse effects of digoxin, a dose of
62.5μg (0.0625 mg) daily or less may suffice.
Neonates, infants and children up to 10 years of age (if cardiac
glycosides have not been given in the preceding two weeks):-
In the newborn, particularly in the premature infant, renal clearance of
digoxin is diminished and suitable dose reductions must be observed, over
and above general dosage instructions.
Beyond the immediate newborn period, children generally require
proportionally larger doses than adults on the basis of body weight or body
surface area, as indicated in the schedule below. Children over 10 years of
age require adult dosages in proportion to their body weight.
Oral loading dose; This should be administered in accordance with the
Preterm neonates < 1.5 kg - 25 μg/kg per 24 hours.
Preterm neonates 1.5 kg to 2.5 kg - 30 μg/kg per 24 hours.
Term neonates to 2 years - 45 μg/kg per 24 hours.
2 to 5 years - 35 μg/kg per 24 hours.
5 to 10 years - 25 μg/kg per 24 hours.
The loading dose should be administered in divided doses with approximately
half the total dose given as the first dose and further fractions of the
total dose given at intervals of 4 to 8 hours, assessing clinical response
before giving each additional dose.
The maintenance dose should be administered in accordance with the following
daily dose = 20 % of 24-hour loading dose (oral).
Term neonates and children up to 10 years:-
daily dose = 25 % of 24-hour loading dose (oral).
These dosage schedules are meant as guidelines and careful clinical
observation and monitoring of serum digoxin levels (see Monitoring) should
be used as a basis for adjustment of dosage in these paediatric patient
If cardiac glycosides have been given in the two weeks preceding
commencement of Lanoxin therapy, it should be anticipated that optimum
loading doses of Lanoxin will be less than those recommended above.
The tendency to impaired renal function and low lean body mass in the
elderly influences the pharmacokinetics of Lanoxin such that high serum
digoxin levels and associated toxicity can occur quite readily, unless doses
of Lanoxin lower than those in non-elderly patients are used. Serum digoxin
levels should be checked regularly and hypokalaemia avoided.
Dose Recommendations in Specific Patients Groups
See Warnings and Precautions.
The serum concentration of digoxin can be determined by radioimmunoassay.
Blood should be taken 6 hours or more after the last dose of Lanoxin. There
are no rigid guidelines as to the range of serum concentrations that are
most efficacious but most patients will benefit, with little risk of toxic
symptoms and signs developing, with digoxin concentrations from 0.8 ng/ml
(1.02 nmol/L) to 2.0 ng/ml (2.56 nmol/L). Above this range toxic symptoms
and signs become more frequent and levels above 3.0 ng/ml (3.84 nmol/L) are
quite likely to be toxic. However, in deciding whether a patient's symptoms
are due to digoxin, the clinical state together with the serum potassium
level and thyroid function are important factors.
Other glycosides, including metabolites of digoxin, can interfere with the
assays that are available and one should always be wary of values which do
not seem commensurate with the clinical state of the patient.
Lanoxin is contra-indicated in intermittent complete heart block or second
degree atrioventricular block, especially if there is a history of
Lanoxin is contra-indicated in arrhythmias caused by cardiac glycoside
Lanoxin is contra-indicated in supraventricular arrhythmias associated with
an accessory atrioventricular pathway, as in the Wolff-Parkinson-White
syndrome, unless the electrophysiological characteristics of the accessory
pathway and any possible deleterious effect of digoxin on these
characteristics have been evaluated. If an accessory pathway is known or
suspected to be present and there is no history of previous supraventricular
arrhythmias, Lanoxin is similarly contra-indicated.
Lanoxin is contra-indicated in ventricular tachycardia or ventricular
Lanoxin is contra-indicated in hypertrophic obstructive cardiomyopathy,
unless there is concomitant atrial fibrillation and heart failure but even
then caution should be exercised if Lanoxin is to be used.
Lanoxin is contra-indicated in patients known to be hypersensitive to
digoxin or other digitalis glycosides.