Leg cramps are a common condition, especially in the elderly. They disrupt sleep and affect overall quality of life. As such, people are happy to find a treatment that works.

Quinine is a medication used commonly to treat nighttime leg cramps, but emerging research has shown it’s unsafe to do so, and experts are advising to find alternative treatment methods [1] [2] [3] [4].

What is Quinine?

Quinine sulfate, at a dose of 200-300 mg at night, was the most commonly drug used to treat nighttime leg cramps for decades. Recently, it was found to be dangerous.

Since there are so many proposed mechanisms to these leg cramps, no single treatment works all the time. Quinine was found to be modestly effective; it reduced the frequency of cramps by 25%, pain by 10% and number of days by 20%. Other medications used for leg cramps are either as good or worse [3].

The Dangers of Quinine

A variety of adverse effects can occur with the usual dosages of quinine, such as [3]:

• Cinchonism: tinnitus, high tone hearing loss, photophobia (discomfort or pain with light exposure) and other visual disturbances, dysphoria (state of unease), headache, nausea, vomiting, sweating, dizziness, postural hypotension
  • conchonism is simply the poisoning due to excessive ingestion of cinchona alkaloids, which are in quinine
• Hypoglycemia: from the drug’s stimulatory effect on pancreatic β cells
• Hypotension: usually related to intravenous infusion of the drug
• Hearing and visual disturbances (including irreversible loss)
• Hastrointestinal symptoms
• Cutaneous (skin) effects

Recommendations Around Quinine [3]

• Not recommended for routine use because of safety concerns
• 4 week trial of quinine could be an option for fully informed patients experiencing frequent severe cramps that disrupt their sleep and quality of life
• Trial should only be considered after treatable causes have been ruled out and non-pharmacological and potentially less toxic pharmacological agents have been tried
• Patients taking quinine beyond 4 weeks should be followed up with and advised periodically to try stopping it

Summary

If you’re taking quinine for nighttime leg cramps, it would be advisable to chat with your doctor about your options. More often, the adverse effects persist and can lead to more severe conditions.