Digoxin renal disease

Digoxin-like immunore active substances (found in patients with chronic heart failure, end stage renal disease, liver disease, or third trimester of pregnancy) may cross-react with certain digoxin immunoassays and may result in a false elevation of levels... 

Renal function impairment In children with renal disease, digoxin must be carefully titrated based upon clinical response. 

Altered tissue binding may also affect the apparent volume of distribution of a drug. For example, the distribution volume of digoxin has been reported to be reduced by 30% to 50% from normal values in patients with renal disease. It has been postulated that this reduction in the distribution volume is secondary to a decrease in tissue... 

Hirata S, Izumi S, Furukubo T, Ota M, Fujita M, Yamakawa T, Hasegawa I, Ohtani H, Sa-wada Y. Interactions between clarithromycin and digoxin in patients with end-stage renal disease. IntJ Clin Pharmacol Ther (2005) 43, 30-36. 

The presence of systemic disease can alter the way an individual detoxifies or excretes a drug. Liver and kidney disease, in particular, can markedly influence drug response by allowing the drug to accumulate to toxic levels. The rate of excretion of digoxin, for example, is reduced considerably in patients with renal impairment, thus causing an increased risk of alterations in color vision in these patients. 

Interference with active transport. Organic acids are passed from the blood into the urine by active transport across the renal tubular epithelium. Penicillin is mostly excreted in this way. Probenecid, an organic acid that competes successfully with penicillin for this transport system, may be used to prolong the action of penicillin when repeated administration is impracticable, e.g. in sexually transmitted diseases, where compliance is notoriously poor. Interference with renal excretion of methotrexate by aspirin, of zidovudine by probenecid and of digoxin by quinidine, contribute to the potentially harmful interactions with these combinations. 

Cautions Autoimmune disease (methyldopa) Orthostatic hypotension Allergy, bradyarrhythmias, coronary spasm, PVD Diabetes mellitus, digitalis toxicity, gout, hyperlipidemias Renal insufficiency, autoimmune diseases, drug interactions with diuretics, digoxin, Li Guanethidine asthma, GI ulcers, renal dysfunction Potent vasodilators > major compensatory fluid retention and cardiac stimulation... 

ECG effects T wave diminished in amplitude or inverted, P-R interval prolonged, Q-T interval shortened. Tests for serum digoxin levels may be altered by electrolyte imbalance, renal impairment, age, thyroid disease, other drugs, or substances in the body which imitate digoxin in radioimmunoassay. 

Elkayam U, I ikh K, Trenal clearance and serum concentratic of digoxin in patients with cardiac disease AmJ... 

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