Beta-alanine in pre-workout can cause itchiness, especially in high doses. This symptom typically resolves within 1 hour. To reduce this, people take split the dose or use a slow release formula.

Beta-alanine is a naturally occurring amino acid in the body. People who work out and athletes may take beta-alanine supplements to help prevent muscle fatigue and increase performance.

Research indicates that when beta-alanine combines with another amino acid called L-histidine, it increases the amount of carnosine in the muscles. Carnosine acts as a PH regulator and reduces the amount of acid in the muscles. In turn, it lessens fatigue that usually comes from high intensity exercise.

This article examines why beta-alanine itch occurs and how to stop it. It also looks at other potential side effects of beta-alanine and the alternatives.

A common side effect of taking beta-alanine is flushing and tingling of the face, hands, or neck. This itching sensation is known as paresthesia.

A 2019 study indicated that this itching could be due to beta-alanine activating G-protein-coupled receptors, which are responsible for transmitting signals throughout the central nervous system, especially on the skin. Additionally, the study concluded that the beta-alanine itch could be associated with the following factors:

  • Ethnicity: Itchiness occurred more frequently in people of Asian descent than Caucasian participants.
  • Sex: Itchiness was more frequent in females than males.
  • Body size: People weighing less than 75 kilograms (kg), or 165 lb, experienced stronger or more frequent itchiness than those weighing more than 85 kg (187 lb).

People of all body weights could tolerate a beta-alanine dose of 6.4 grams (g) if they did not take it for longer than 24 weeks. The itchiness was more likely to occur when people took a dose of 40 milligrams (mg) per 1 kg (2.2 lb) of body weight. However, the itchiness was milder or less intense when people took doses of 10–20 mg per 1 kg (2.2 lb) of body weight.

Some people may experience less itchiness when they take beta-alanine as part of a multi-ingredient pre-workout supplement in powder form, compared with beta-alanine alone. This is because the mixture of substances may cause a slower release into the bloodstream.

A 2021 study investigated the effects of using a high dose beta-alanine powder on a small group of world cyclists to maintain high intensity performance after a week of intensive training camps. The researchers gave the cyclists 20 g of beta-alanine daily for 1 week.

Itchiness occurring from the beta-alanine lasted for approximately 1 hour. The researchers noted that higher doses of beta-alanine increased the chance of experiencing paresthesia.

The only remedy for getting rid of beta-alanine-related paresthesia is to wait for the side effects to subside. Research suggests that the beta-alanine itch reduces after about 1 hour.

However, people can prevent beta-alanine paresthesia by taking beta-alanine as a sustained-release powder or tablet or splitting the dose into smaller quantities throughout the day. People should ensure they do not exceed the suggested maximum dose of 6.4 g of beta-alanine over 24 weeks.

Paresthesia is the most commonly researched side effect of using beta-alanine.

However, some studies suggest that beta-alanine may reduce plasma and muscle-free histidine availability, which may affect muscle protein synthesis. A 2019 meta-analysis found no evidence of this side effect, but the authors said they could not rule it out.

People naturally produce beta-alanine in their liver. However, they can also obtain it through diet.

Food sources that contain small amounts of beta-alanine include:

People who eat meat have an intake of about 1 g of beta-alanine per day, compared to vegans who have no intake. In both cases, people would have to take supplementation when using beta-alanine to enhance athletic performance.

People could choose pre-workout supplements such as creatine as an alternative to beta-alanine. However, it is important to note that these supplements do not work in the same way.

Researchers conducted a study on 32 elite athletes in an 8-week trial to investigate whether using an alkaline agent with a branched-chain amino acid (BCAA) and creatine malate (Cr) would be as effective as using beta-alanine in combination with BCAAs and Cr to improve endurance. The results showed beta-alanine to be more effective than the alkaline agent when combined with BCAAs and Cr.

Fitness enthusiasts and athletes may take beta-alanine as a supplement to help improve performance and lessen muscle fatigue. However, when people consume beta-alanine at a high dose, they risk getting paresthesia.

Paresthesia is a tingling or itching sensation that lasts around 1 hour and subsides on its own. People can avoid this side effect by splitting the dose of beta-alanine or using sustained-release powders and tablets.

People may use alternatives to beta-alanine. These alternatives include fish, meat, and poultry that contain small amounts of beta-alanine. Additionally, people may use creatine supplements. However, creatine does not work the same as beta-alanine.