What is a charley horse?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
A charley horse is nothing more than a muscle spasm that, while quick and harmless, can still be very painful. Muscle spasms commonly occur when your electrolytes are imbalanced, you’re dehydrated, or that muscle is overworked. For instance, when muscles suddenly contract, your body’s electrolytes can become imbalanced, causing nerves to fire uncontrollably. This is when charley horses happen.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.