One connection between digitalis and potassium relates to how both substances affect heart contractions and kidney function. Another link between digitalis and potassium centers on the risk of digitalis toxicity if potassium levels fall too low. Some patients who take digitalis for congestive heart failure also use diuretics to prevent fluid retention. These drugs might also affect digitalis and potassium levels in the bloodstream by depleting this essential mineral.
Digitalis toxicity might occur from a single, high dose of the drug or when a patient builds up tolerance to the medication over time. Too much digitalis might lead to overproduction of urine or trouble urinating, with both conditions affecting potassium, which is excreted through the kidneys. Certain heart conditions might also hinder normal kidney functioning, leading doctors to monitor digitalis and potassium levels on a regular basis.
Chemicals from some parts of the poisonous Digitalis lanata plant are used to make digoxin, a medication used to treat heart failure and irregular heart rhythms. The drug might allow stronger contractions of the heart to increase blood flow. Digitalis also reduces fluid retention by increasing the output of urine. Increased urination might lead to low levels of potassium and magnesium.
This connection between digitalis and potassium is commonly seen when diuretics make up part of the treatment plan for heart patients. These medications might deplete potassium by increasing urination, which might lead to digitalis toxicity. Other medications that affect the kidneys, such as quinine, might produce similar effects.
Signs of toxicity include various vision problems. Vision might become blurred or blind spots might be present. Some patients report that colors seem off and objects take on a yellow tinge. Halos around lights or seeing spots of light represent common complaints when digitalis reaches toxic levels, along with decreased pupil size.
Patients might also produce very little urine or need to urinate several times during the night. Swelling might occur if too much fluid is retained, and some patients experience trouble breathing, especially when prone. Doctors typically monitor kidney function, along with digitalis and potassium levels through frequent blood tests when the drug is prescribed.
Potassium supplements when using digitalis might balance levels of the mineral, especially when also using diuretics. The heart relies on potassium for contractions, making this a vital element for patients who suffer congestive heart failure. Patients who combine digitalis with certain antibiotics or stimulant laxatives might also increase the risk of side effects if potassium levels fall too low.