DIGOXIN (LANOXIN ®)

Usual Diluents

NS,   D5W

Standard Dilutions   [Amount of drug]  [Infusion volume]  [Infusion rate]

[All doses/ 50 ml] [15 min]

Stability / Miscellaneous

Immediate use is recommended. Minimum of a 4-fold dilution.  Loading dose: CHF: 8-12 mcg/kg in divided doses (q4-8h) over 12 to 24 hours. [Normally, give 50% of the total digitalizing dose in the initial dose, then give 25% of the total dose in each of the two subsequent doses at 8 to 12 hr intervals--Obtain EKG 6 hours after each dose to assess potential toxicity (AV block, sinus bradycardia, atrial or nodal ectopic beats, ventricular arrhythmias); Other: vision changes, confusion.]    If pt has renal insufficiency give 6 to 10 mcg/kg IBW.  A-fib: 10 to 15 mcg/kg IBW given as above. (If given IVPush - administer over at least 5 minutes).   Maintenance dose: Digoxin clearance= [CRCL + 40] x 1.44 (add 20 instead of 40 if pt has CHF).    Predicted Css= (Dose) (0.65 to 0.8)/ Digoxin clearance. Alternatively, maintenance dose= Loading dose x [0.14 x crcl / 500 ]    Avoid IM injections-can lead to severe pain (If it must be given by this route, give deep IM followed by massage). Monitoring: Obtain blood samples at least 4 hours after IV dose and 6-8hours after oral dose. Serum levels: 0.5 to 2.5 ng/ml     Onset/peak:   IV: 5-30min/ 1-4hours          Oral: 1-2hours/ 2-8 hours.  Time to steady state: 5-7 days (average) ESRD: 15-20 days.  Half-life: 38-48 hours. (anephric: 4-6 days).  Conversion from oral to IV: Decrease IV dose by 20 to 25%. When the maintenance dose is given IV, the onset and peak will occur earlier, however the duration of action is the same. Patients' on the "floors" may receive once daily IV maintenance doses, however, IV loading regimens (multiple doses) are restricted to patients on a monitor- ICU's. [Oral bioavailability (tablets): 70 to 80%].