- See:
- EKG Changes
- Interactions and Toxicities:
- Discussion:
- for CHF, A.fib, flutter, PAT;
- digitalis is the only drug that slows ventricular response w/o decreasing myocardial contractility;
* Adult Dosing:
* Loading: 0.25 - 0.5 PO/IV, then .25mg PO q6hr, until total dose = 1.0-1.5mg;
* Note onset of action = 30min IV, 2hr PO; w/ normal Renal function:
* Daily dose = 0.125- 0.5mg PO,IV,IM qd;
* Theraputic Digoxin dose = 0.8 - 2.0 ng/ml; > than 2.4=toxic;
* Theraputic Digitoxin dose = 13.0 - 25.0 ng/ml; > 40 is toxic;
- Use in A. Fib
- onset of IV digoxin takes as long as 30 min. and peaks at 90-120 min
- therefore, digoxin should not be given at intervals less than 2 hrs;
- some patients may not slow with the initial 0.5 mg IV dose;
- best indicator of successful of digitalization is ventricular rate;
- w/ atrial fibrillation, digoxin is given until the rate is controlled to < 120;
- Precautions: (see interactions)
- w/ Digoxin Toxicity and Hypo K may try 80 mEq KCl IV may be given in 1 liter of D5W at 6 ml/min (0.5 mEq/min);
- initial therapy of toxicity related arrhythmias includes LIDOCAINE & dilantin;
- calcium is contraindicated and Cardioversion should be avoided;
- Peds:
- Digitalization: 65-75 ug/kg PO or 50 ug/kg IV; 1/2 total dose initially then 1/4 of total q8-12hr for 2 doses;
- Maintenance: 15-20 ug/kg/day PO divided q12hr; 2-10 yrs:
- Digitalization: 30-40 ug/kg PO or 25 ug/kg IV given as above;
- Maintenance: 8-10 ug/kg/day PO or divided q12hr