Conditions and symptoms
What Is Hypokalemia? Low Potassium
Hypokalemia · say it: hy-po-kuh-LEE-mee-uhAlso written: low potassium, hypokalaemia, low blood potassium
Short answer
Hypokalemia means the level of potassium in the blood is lower than expected. Some medicines, like many diuretics, can cause it.
What it means
Hypokalemia means there is too little potassium in the blood. Potassium helps nerves and muscles work, including the heart muscle. Mild hypokalemia often causes no symptoms. Lower levels can cause weakness, cramps, constipation, tiredness or an irregular heartbeat. Palpitations, severe weakness or fainting need urgent medical help.
Labels list hypokalemia for medicines that make the body lose potassium, such as many diuretics (water pills), some asthma medicines in high doses, corticosteroids and laxatives used heavily. It also appears on labels for medicines that affect heart rhythm, because low potassium can make rhythm problems more likely. The warning is telling your doctor to check your potassium and telling you to report cramps, weakness or palpitations.
Hypokalemia (low potassium) is the opposite of hyperkalemia (high potassium). Both can affect the heart, which is why potassium is checked in routine blood tests called electrolytes or U&E.
Where you may see it
- Diuretic labels and leaflets
- Blood test reports as 'Potassium (K)' with an L flag
- Warnings on medicines that affect heart rhythm
📄 How it looks on a report
Potassium (K): (L) Below reference range.
🙅 What it does not mean
- It does not mean you should start potassium tablets or salt substitutes on your own; ask your doctor.
- A slightly low result does not always need urgent treatment.
- It is not the same as hyperkalemia, which is high potassium.
🎯 Check yourself
Which of these is the right meaning of “Hypokalemia”?
🗒️ Questions to ask your doctor
💊 Medicines whose labels mention “Hypokalemia”
Plain-English explanations of each medicine, from its official FDA label.
- Albuterol
A bronchodilator (a medicine that opens the airways) of the beta-2 adrenergic type. The FDA class is not listed, so this description comes from the label's own wording.
- Artemether and Lumefantrine
an antimalarial medicine, which is a fixed combination of two blood-stage antimalarial ingredients (artemether, an artemisinin derivative, and lumefantrine)
- Ciprofloxacin
a fluoroquinolone antibacterial medicine
- Citalopram
a selective serotonin reuptake inhibitor (SSRI), a type of antidepressant medicine
- Fluconazole
an azole antifungal medicine, a type of medicine that treats fungal (yeast) infections
- Furosemide
A loop diuretic, a type of medicine that helps the body get rid of extra fluid through urine
- Hydrochlorothiazide
A thiazide diuretic, a type of medicine often called a 'water pill'
- Hydroxychloroquine
an antimalarial and antirheumatic drug, which means it is used for malaria and for certain joint and immune conditions
- Insulin Glargine
an insulin analog, a long-acting man-made insulin used to treat diabetes
- Levofloxacin
an antibiotic of the fluoroquinolone type
🔗 Read more from trusted sources
- “Hypokalemia” on MedlinePlus ↗
US National Library of Medicine
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