l-carnitine injection indication | Linus Pauling Institute How To Inject L Carnitine:
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10.1111/j.1365-2605.2011.01226.x 77 PaulisG.BrancatoT.D'AscenzoR.De GiorgioG.NupieriP.OrsoliniG.et al (2013)

And as much as possible take less preservatives

In general, a dose of 500mg is administered 30 minutes before a workout

Matsuoka AJ, Morrissey ZD, Zhang C, et al
