What supplements can cause muscle twitching?

From the Guidelines

Beta-alanine supplements can cause muscle twitching, specifically transient paresthesia, as a side effect, particularly at high doses. This is according to a 2021 study published in the British Journal of Sports Medicine 1. The study notes that beta-alanine may improve high-intensity exercise and repeated sprint performance but can cause skin rashes and/or transient paresthesia. Some key points to consider when taking beta-alanine supplements include:

• The recommended daily consumption is ~65 mg/kg BM, ingested via a split-dose regimen to give up to 6.4 g/day over an extended supplement timeframe of 4–12 weeks 1.
• The protocol requires planning alongside training and match loads, and further investigation is required into long-term supplementation (ie, >12 weeks) 1. Other supplements like nitrate may have individual responses to supplementation and possibilities of minor gastrointestinal upset, but they are not directly associated with muscle twitching 1. It is essential to exercise extreme caution when considering supplements, especially in team sports, due to the risk of anti-doping rule violations and potential side effects like muscle twitching 1.

From the Research

Supplements Known to Cause Muscle Twitching

There are several supplements that can cause muscle twitching, although the evidence is not always clear-cut. Some supplements may have adverse effects, including muscle twitching, especially when taken in large doses.

• Magnesium supplements: While magnesium is often used to prevent muscle cramps, high doses can cause adverse effects, including muscle twitching 2.
• Beta-alanine: This supplement can cause paresthesia, a tingling sensation in the skin, which may be mistaken for muscle twitching 3.
• Caffeine: High doses of caffeine can cause muscle twitching, as well as other adverse effects such as jitteriness and anxiety 4, 3.
• Creatine: While creatine is generally considered safe, high doses can cause muscle cramps, spasms, and twitching 4, 3.
• Other supplements: Other supplements, such as branched-chain amino acids, adenosine triphosphate, citrulline, β-Hydroxy-β-methylbutyrate, minerals, most vitamins, phosphatidic acid, or arginine, may also cause muscle twitching, although the evidence is limited or unclear 5.

Mechanisms of Muscle Twitching

The mechanisms of muscle twitching caused by supplements are not always clear. However, some possible mechanisms include:

• Electrolyte imbalance: Supplements that affect electrolyte balance, such as magnesium, can cause muscle twitching by disrupting the normal functioning of muscle cells 2.
• Neurotransmitter modulation: Supplements that affect neurotransmitter levels, such as caffeine, can cause muscle twitching by altering the normal functioning of the nervous system 4, 3.
• Muscle cell damage: Supplements that cause muscle cell damage, such as high doses of creatine, can cause muscle twitching by disrupting the normal functioning of muscle cells 4, 3.