Effect of slow-release β-alanine tablets on absorption kinetics and paresthesia

Abstract

Oral β-alanine (βA) doses larger than 800 mg commonly result in unpleasant sensory symptoms (paresthesia). However, the association of form (pure vs. slow-release) with side-effects has not been fully described. The aim of this single-blinded, randomized three-arm clinical trial was to compare plasma kinetics and symptoms following βA bolus administration in solution or in slow-release tablet form. Eleven healthy adults ingested 1.6 g of a pure βA reference solution (REF), 1.6 g in slow-release βA tablets (TAB) or a placebo (PLA) after an overnight fast. During the next 6 h, urinary and plasma βA concentrations were measured and questionnaires about intensity, nature (pins and needles, itching, flushing, irritation, numbness, soreness), and spatial distribution of unusual sensations were filled in. TAB resulted in a smaller peak plasma concentration than REF (82 vs. 248 μmol L(-1), p<0.001), delayed time to peak (1.0 vs. 0.5 h, p<0.01) no difference in area under the curve, reduced loss in urine (202 vs. 663 μmol, p<0.0001), and improved retention (98.9 vs. 96.3%, p<0.001). Symptoms described as "pins and needles" were perceived rapidly on the skin of the arms and trunk after REF (Tmax=15 min) and their time course nearly mimicked plasma concentrations. Maximum intensity scores were weaker with TAB ("very low") than with REF ("low", p<0.001), while TAB and PLA did not differ with respect to side-effects. In summary, ingesting 1.6 g βA in slow-release tablets rather than pure in solution results in slower absorption kinetics, improved whole body retention and sensory side-effects that cannot be differentiated from PLA.

Effect of β-alanine supplementation on 20 km cycling time trial performance

“…e sustained-release formulation of β-alanine used in the present study has been shown to reduce the symptoms of paraesthesia often associated with individual doses of β-alanine administered as free powder 22 . In this study, none of the participants reported any feelings of paraesthesia, and we are con dent that the integrity of the double blinding was maintained.…”

Effect of two β-alanine dosing protocols on muscle carnosine synthesis and washout

“…It has previously been demonstrated that this slow-release tablet of BA results in a blunting of peak plasma BA with similar area under the curve compared to pure BA (Decombaz et al 2011;Harris et al 2008). This slow-release BA still reaches plasma concentrations above the BA transporter K m of *40 lM (Bakardjiev and Bauer 1994) and thus would be hypothesized to be effective for muscle carnosine synthesis.…”

“…1). These questionnaires included a body surface symptoms score (SSS), profile of mood states (POMS) and a state anxiety inventory (SAI), and are fully described by Decombaz et al (2011). The flushing symptoms questionnaire (FSQ) was developed specifically for this study, and was a 10-question retrospective questionnaire focusing on any unusual skin or paresthesia symptoms, and the intensity and duration of symptoms, in the previous 24 h. Questions on ''warmth'', ''redness'', ''pins and needles'' and ''itching'' on a 5-point scale (from none to weak to moderate to strong or extremely strong) were included.…”

“…Given this, most studies have implemented small repeated daily doses of B800 mg (as much as 8 individual doses; up to 6.4 g/day) to minimize paraesthesia symptoms (Derave et al 2007;Hill et al 2007;Kendrick et al 2008). Recently, a commercialized slow-release tablet of BA has been produced and it was demonstrated that a single 1.6 g BA dose resulted in a blunting of the peak plasma curve with no reports of any paresthesia symptoms in any subjects (Decombaz et al 2011;Harris et al 2008). However, the efficacy of muscle carnosine synthesis with the slowrelease BA tablet remains to be investigated.…”

The Effect of 28 Days of Beta-alanine Supplementation on Exercise Capacity and Insulin Sensitivity in Individuals with Type 2 Diabetes Mellitus: A Randomised, Double-blind and Placebo-controlled Pilot Trial

“…Slow release BA was not available, therefore four grams of BA or placebo was split in to three separate doses per day to minimise the paraesthesia associated with BA consumption above 800 mg per dose [9,16] Maltodextrin was chosen due to its close appearance to BA and to remain consistent with BA double-blind randomised and placebo-controlled trials [17][18][19][20]. The dose used in this trial was not considered high enough to elicit a heighted insulin response or elevate fasting blood sugar.…”