While potassium is a nutrient we get from food, diet alone rarely causes hypokalemia. There are several possible causes of hypokalemia and certain populations who have an increased risk of deficiency. These include:. Certain medications can also cause low potassium levels, including:.
Hypokalemia can contribute to, or cause other health issues, including:. Very low potassium levels can cause more severe health conditions, such as heart rhythm problems, and can cause your heart to stop. In mild cases of hypokalemia, potassium levels can normalize within a few days after you start increasing potassium intake. Making sure you eat enough potassium-rich foods every day can help boost and maintain healthy potassium levels. Taking supplements, however, can be risky.
Potassium supplements might cause minor gastrointestinal side effects or very high levels of potassium. Over-the-counter supplements might not be enough if your potassium level is extremely low. The FDA limits supplements to less than mg of potassium, which is only a fraction of the daily recommended intake. Although it has long been established that the maintenance of normal serum potassium is essential in reducing the risk of life-threatening cardiac arrhythmias, accumulating evidence suggests that the increased intake of potassium can also lower blood pressure and reduce the risk of stroke.
Few clinicians attempt to monitor and augment potassium stores on a routine basis. One reason may be the inconvenience of accurately measuring total body potassium, which entails a hour urinary collection rather than a rapid laboratory serum measurement.
Another reason is the practical difficulty of achieving and maintaining optimal potassium levels. Therefore, many clinicians may not attempt to remedy subnormal potassium levels except in high-risk patients. The current lack of consensus on how to prevent and treat hypokalemia has led to the neglect of a wide range of situations in which increasing potassium intake might help prevent sequelae of cardiovascular disease.
The multifactorial and interactive mechanisms that are stimulated by hypertension and even more so by heart failure, which mandate the introduction of drugs that disrupt electrolyte homeostasis, emphasize the serious role of potassium.
This article reviews contemporary thinking on potassium in clinical practice. Normal serum potassium levels are considered to lie roughly between 3. Whereas it is generally accepted that diuretic therapy can decrease serum potassium to hypokalemic levels, the subtler effects of inadequate dietary potassium are less well known. For instance, although young adults may consume up to mg 85 mmol of potassium per day, many elderly individuals, particularly those living alone or those who are disabled may not have a sufficient amount of potassium in their diet.
Urban whites typically consume approximately mg In contrast, many African Americans have low intakes of about mg 25 mEq per day. Factors that affect potassium intake include the type of diet consumed Table 1 , age, race, and socioeconomic status. Potassium depletion is one of the most common electrolyte abnormalities encountered in clinical practice.
Increases in insulin or catecholamines can also stimulate cells to import potassium and export sodium. In patients with type 2 diabetes, increases in glucose or insulin can affect potassium homeostasis. A standard dose of nebulized albuterol reduces serum potassium by 0.
Overt hypokalemia may be diagnosed when the serum potassium level is less than 3. Potential causes include diuretic therapy, inadequate dietary potassium intake, high dietary sodium intake, and hypomagnesemia Table 2.
In most cases, hypokalemia is secondary to drug treatment, particularly diuretic therapy Table 3. Management of hypokalemia should begin with a thorough review of the patient's medical record. If potassium-wasting drugs are not implicated, hypokalemia is most commonly caused either by abnormal loss through the kidney induced by metabolic alkalosis or by loss in the stool secondary to diarrhea. Because potassium is a major intracellular cation, the tissues most severely affected by potassium imbalance are muscle and renal tubular cells.
Manifestations of hypokalemia include generalized muscle weakness, paralytic ileus, and cardiac arrhythmias atrial tachycardia with or without block, atrioventricular dissociation, ventricular tachycardia, and ventricular fibrillation.
Typical electrocardiographic changes include flat or inverted T waves, ST-segment depression, and prominent U waves. In severe untreated hypokalemia, myopathy may progress to rhabdomyolysis, myoglobinuria, and acute renal failure.
Such complications are most often seen in hypokalemia secondary to alcoholism. Data from animal experiments and epidemiologic studies suggest that high potassium may reduce the risk of stroke. Although part of the protective effect of potassium may be due to lowering of blood pressure, analysis of animal models suggests that potassium may have other protective mechanisms, including inhibitory effects on free radical formation, vascular smooth muscle proliferation, and arterial thrombosis.
This apparent protective effect of potassium was independent of other nutritional variables, including energy caloric intake; dietary levels of fat, protein, and fiber; and intake of calcium, magnesium, and alcohol. The authors also noted that the effect of potassium was greater than that which would have been predicted from its ability to lower blood pressure. More recently, Ascherio et al 6 reported the results of an 8-year investigation of the association between dietary potassium intake and subsequent risk of stroke in 43, US men, aged 40 to 75 years, without previously diagnosed cardiovascular disease or diabetes.
During the study follow-up, strokes were documented. The relative risk of stroke for men in the top fifth of the range of potassium intake median intake, 4. The inverse association between potassium intake and subsequent stroke was more marked in hypertensive men and was not significantly altered by adjustment for baseline level of blood pressure. Ascherio et al 6 also found that the use of potassium supplements was inversely related to the risk of stroke, particularly among hypertensive men.
They speculated that this relationship might be due, at least in part, to a reduction in the risk for hypokalemia. Evidence from epidemiologic and clinical studies has implicated potassium depletion in the pathogenesis and maintenance of essential hypertension. These syndromes are characterized by abnormally low serum potassium levels and elevated blood pressure.
Reversal of the underlying cause results in increased serum potassium levels and decreased blood pressure. Similarly, correction of diuretic or laxative abuse can also raise potassium level and lower blood pressure. Specifically, intake of potassium-rich fruits and vegetables was inversely related to systolic and diastolic pressure.
Whelton et al 21 recently conducted a meta-analysis of randomized controlled trials evaluating the effects of oral potassium supplementation on blood pressure.
This analysis included 33 clinical trials involving participants. In these trials, the use of potassium supplementation was the only difference between the intervention and control arms.
The results demonstrated that potassium supplementation was associated with a significant reduction in mean systolic and diastolic blood pressure —4. The greatest effects were observed in participants who had a high concurrent sodium intake.
This analysis suggests that low potassium intake may play an important role in the genesis of high blood pressure. Thus, the authors recommended increased potassium intake for the prevention and treatment of hypertension. Among hypertensive patients, certain subgroups would derive special benefit from increased potassium intake. Best recognized are African Americans. In addition, several studies have revealed lower urinary potassium excretion in blacks than in whites.
The urinary sodium-to-potassium ratio was 4. The study concluded that the difference in urinary potassium excretion and in serum potassium levels between blacks and whites reflected a difference between the 2 groups in the intake of dietary potassium. Such a difference may be an important factor in the greater prevalence of hypertension in blacks.
Not surprisingly, potassium depletion is commonly seen in patients with CHF, a condition that is characterized by several physiologic abnormalities that predispose to the development of electrolyte disturbances. Among the pathogenetic factors associated with CHF are renal dysfunction and neurohormonal activation, which embrace stimulation of the renin-angiotensin-aldosterone axis, enhanced sympathetic nervous tone, and hypersecretion of catecholamines. A common misperception regarding angiotensin-converting enzyme ACE inhibitor therapy is that these drugs enhance potassium retention, thereby eliminating the need to add potassium or potassium-sparing diuretics to ACE inhibitor therapy.
In many cases, the prescribed dosages of ACE inhibitors in patients with CHF are insufficient to protect against potassium loss. Serum potassium levels, therefore, must be closely monitored in all patients with CHF—even those taking ACE inhibitors—to minimize the life-threatening risk of hypokalemia in these patients.
The arrhythmogenic potential of digoxin is enhanced by hypokalemia in patients with heart failure. When using digoxin in combination with a loop diuretic and an ACE inhibitor, the decision of whether to administer potassium supplements can be complex. Leier et al 26 recommend maintaining serum potassium levels in the range between 4. Drink the mixture slowly, over 5 to 10 minutes in all. To make sure you get the entire dose, add a little more water to the same glass, swirl gently and drink right away.
Your treatment may include a special diet. It is very important to follow the diet plan created for you by your doctor or nutrition counselor. You should become very familiar with the list of foods you should eat or avoid to help control your condition. Store potassium citrate at room temperature away from moisture and heat. Keep the medication in a closed container. Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose.
Do not take extra medicine to make up the missed dose. Overdose symptoms may include heavy feeling in your arms or legs, muscle weakness, limp feeling, slow or uneven heartbeat, chest pain, or feeling like you might pass out. Avoid taking potassium supplements or using other products that contain potassium without first asking your doctor. Salt substitutes or low-salt dietary products often contain potassium. If you take certain products together you may accidentally get too much potassium.
Read the label of any other medicine you are using to see if it contains potassium. While taking this medication, avoid strenuous exercise if you are not in proper condition for it. Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using this medication and call your doctor at once if you have any of these serious side effects:.
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. The following drugs can interact with potassium citrate. Tell your doctor if you are using any of these:. This list is not complete and there may be other drugs that can interact with potassium citrate. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors.
Do not start a new medication without telling your doctor. A more serious indication of hypokalemia is abnormal heart rhythms. According to the Mayo Clinic, most cases of low potassium are detected by accident when you get a blood test for something else. If the deficiency is severe, potassium levels need to be elevated quickly, something which has to be done under a doctor's supervision.
DeVita says. Part of the reason is to avoid a potassium overload, or hyperkalemia, which can have equally dangerous consequences. Then the underlying causes need to be addressed. Nutrition Nutrition Basics Vitamins and Supplements.
By Amanda Gardner Updated January 22,
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