Digoxin toxicity

Because some patients are more sensitive to side effects with digoxin, the dosage is selected carefully and adjusted as the clinical condition indicates. Adverse reactions were more common and severe in past years before careful attention to weight, renal function, and the concurrent administration of certain medications was given. The incidence and severity of digoxin toxicity has decreased significantly in recent years. 

Most often digoxin toxicity can be successfully treated by simply wididrawing die drug. However, severe life-direatening toxicity is treated widi digoxin immune fab... 

Which drug would the nurse expect to be prescribed for a patient with digoxin toxicity ... 

Lloyd, B.L., and Smith, T.W. Contrasting rates of reversal of digoxin toxicity by digoxin-specific IgG and Fab fragments. 

Avoid if suspected digitalis toxicity. If severe symptomatic hyperkalemia and concomitant digoxin toxicity, treat with Digibind prior to infusing calcium if time permits... 

The findings of hypomagnesemia include muscle weakness, cramps, agitation, confusion, tremor, seizures, ECG changes (increased PR interval, prolonged QRS complex, and increased QT interval), findings of hypocalcemia (see above), refractory hypokalemia (see above), metabolic alkalosis, and digoxin toxicity.42,47,48... 

Increased age is most likely associated with enhanced susceptibility to digoxin toxicity, possibly due to unknown pharmacodynamic changes, even when plasma concentrations are within therapeutic range (Miura et al. 2000). 

In a screening system used for potential new drugs, acesulfame K was inert in all test systems except where potassium has an effect, like a transient influence on blood pressure after injection or reduction of digoxin toxicity.7... 

Itraconazole is a triazole antifungal, which increases the plasma concentration of digoxin, hence increasing the risk of digoxin toxicity. 

Digoxin adverse reactions are dose-dependent and occur at doses higher than those needed to achieve a therapeutic effect. Cardiac adverse reactions accounted for approximately 50%, Gl disturbances for approximately 25%, and CNS and other toxicity for approximately 25% of these adverse reactions. However, available evidence suggests that the incidence and severity of digoxin toxicity has decreased substantially in recent years. 

If you have done some clinical work you may have noticed that digoxin tablets come in two dose sizes - 0.25 mg (usually white), and 0.0625 mg (or 62.5 microgram - often blue in colour). One brand name is Lanoxin PG . Did you know that the PG stands for paediatric-geriatric which recognizes the immature kidneys of the infant and the failing kidneys of the elderly and the need to give smaller doses at both ends of life to avoid digoxin toxicity ... 

Digoxin Reduced digoxin levels digoxin toxicity seen in one patient when St John s wort stopped... 

Contraindications Calcium renal calculi, digoxin toxicity, hypercalcemia, hypercalci-uria, sarcoidosis, ventricular fibrillation... 

The most common early manifestations of digoxin toxicity are G1 disturbances (anorexia, nausea, vomiting) and neurologic abnormalities (fatigue, headache, depression, weakness, drowsiness, confusion, nightmares). 

Diuretics may induce hypokalemia, which sensitizes the heart to digoxin toxicity and stops the tubular excretion of the drug. Toxicity has gastrointestinal (nausea,... 

Digoxin at high levels can cause confusion and sedation in the elderly but Mrs GG does not present with confusion. Also digoxin toxicity can cause arrhythmias or bradycardia which can result in a drop in cardiac output leading to a fall. Again she does not presently exhibit any symptoms of digoxin toxicity so this is unlikely. A digoxin serum level may be useful to confirm this. 

PROPAFENONE CARDIAC GLYCOSIDES Digoxin concentrations may be t by propafenone Uncertain at present Watch for digoxin toxicity check digoxin levels if indicated and 1 digoxin dose as necessary (15-75% suggested by studies)... 

ACE INHIBITORS DIGOXIN t plasma concentrations of digoxin when captopril is co-administered in the presence of heart failure (class II or more severe) or renal insufficiency. No other ACE inhibitors seem to interact in the same way Uncertain postulated to be due to 1 renal excretion of digoxin Monitor digoxin levels watch for digoxin toxicity... 

CARVEDILOL DIGOXIN Carvedilol may t digoxin plasma concentrations, particularly in children i P-gp-mediated renal clearance of digoxin 1 the dose of digoxin by 25% watch for signs of digoxin toxicity and monitor digoxin levels... 

DIGOXIN NS AIDS Diclofenac, indometacin and possibly fenbufen, ibuprofen and tiaprofenic acid t plasma concentrations of digoxin and t risk of precipitating cardiac failure and renal dysfunction Uncertain postulated that NSAID-induced renal impairment plays a role however, since all NSAIDs have this effect, it is not understood why only certain NSAIDs actually influence digoxin levels Monitor renal function closely. Monitor digoxin levels watch for digoxin toxicity... 

DIGOXIN OPIOIDS T concentrations of digoxin may occur with tramadol Uncertain at present Watch for digoxin toxicity check levels and i the dose of digoxin as necessary... 

DIGOXIN MACROLIDES Digoxin concentrations may be t by macrolides Uncertain postulated that macrolides inhibit P-gp in both the intestine (t bioavailability) and kidney (i clearance). It is possible that alterations in intestinal flora may also have a role Monitor digoxin levels watch for digoxin toxicity... 

DIGOXIN CICLOSPORIN t plasma digoxin levels, with risk of toxicity. Digoxin may t cidosporin bioavailability (by 15-20%) Attributed to inhibition of intestinal P-gp and renal P-gp, which t bioavailability and t renal elimination. Digoxin t bioavailability of cidosporin due to substrate competition for P-gp Watch for digoxin toxicity. Monitor plasma digoxin and cidosporin levels... 

DIGOXIN CORTICOSTEROIDS Risk of digoxin toxicity due to hypokalaemia Corticosteroids may cause hypokalaemia Monitor potassium levels closely. Monitor digoxin levels watch for digoxin toxicity... 

DIGOXIN TACROLIMUS Digoxin toxicity (pharmacodynamic) Possibly due to tacrolimus-induced hyperkalaemia and hypomagnesaemia Watch for digoxin toxicity. Monitor potassium and magnesium levels... 

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