Side Effect: Low Blood Potassium (hypokalemia)

What is Low Blood Potassium (hypokalemia)?

Low blood potassium, or hypokalemia, is a condition where the level of potassium in the blood is below normal range (normal range = 3.5 to 5.0 mEq/L). A level below 3.5 mEq/L is considered low.

What does Low Blood Potassium (hypokalemia) look like?

Potassium is an electrolyte that is important for many bodily functions including muscle function, nerve function, heart rhythm regulation, and fluid balance. When potassium levels drop too low, it can cause muscle weakness, muscle cramps, heart palpitations, and even life-threatening arrhythmias. Low blood magnesium, or hypomagnesemia can also occur with and may worsen low blood potassium.

Who gets Low Blood Potassium (hypokalemia)?

Anyone can develop low blood potassium, but some people may be more at risk than others. Those who have conditions such as chronic kidney disease, heart failure, alcoholism, adrenal insufficiency, and certain gastrointestinal disorders, are at higher risk. Additionally, patients with cancer are at high risk of developing low blood potassium due to poor nutrition, chemotherapy-induced vomiting and diarrhea, and chemotherapy.

Some of the causes of low blood potassium include:

• Loss of potassium through urine, sweat, vomiting or stool
• Low potassium in your diet
• Hyperaldosteronism
• Fanconi’s syndrome
• Insulin
• Beta2-agonists: albuterol (Ventolin®, Proventil®), epinephrine (Adrenalin®, EpiPen®), salmeterol (Serevent®)
• Loop diuretics, also may be called “water pills”: furosemide (Lasix®), torsemide (Demadex®), bumetanide (Bumex®)
• Penicillin antibiotics: nafcillin, ampicillin, penicillin
• Thiazide and thiazide-like diuretics: hydrochlorothiazide (HCTZ), metolazone (Zaroxolyn®, chlorthalidone (Thalitone®)
• Aminoglycoside antibiotics: amikacin, gentamicin, tobramycin
• Laxatives
• Caffeine
• Corticosteroids: hydrocortisone (Cortisone®), fludrocortisone (Florinef®), prednisone (Deltasone®)

Some cancer treatments that can cause low blood potassium include:

• Platinum therapy: cisplatin (Platinol®), carboplatin (Paraplatin®)
• Ifosfamide (Ifex®)
• EGFR inhibitors: cetuximab (Erbitux®), panitumumab (Vectibix®)
• mTOR inhibitors: temsirolimus (Torisel®), everolimus (Afinitor®)
• Antimetabolites: methotrexate (Trexall®), pemetrexed (Alimta®, Pemfexy®), azacytidine (Vidaza®)
• Antiandrogen: abiraterone (Zytiga®)
• Octreotide (Sandostatin®)

How to prevent Low Blood Potassium (hypokalemia)

To prevent low blood potassium, it is important to maintain a healthy diet that includes food rich in potassium such as bananas, potatoes, avocados and spinach. People who are at risk of low blood potassium due to certain medical conditions should also be monitored regularly by their healthcare provider to ensure that their potassium levels remain within a normal range.

How to treat Low Blood Potassium (hypokalemia)

The main goal of treatment is to prevent or treat life-threatening complications and replace the potassium that has been lost with intravenous (IV) or oral potassium. In some cases, if magnesium is low, this can make replacing potassium difficult. It is important to test for low blood magnesium when low blood potassium is present. If the magnesium in the blood is also low, IV or oral magnesium may be given.