Most well-formulated copper peptide scalp serums that include both will have them in a combined formula
You can make finer dose adjustments (like stepping from 0.5 mg to 0.75 mg instead of jumping straight to 1.0 mg) and you can use split dosing strategies that pre-filled pens do not allow
Ferrari R, Merli E, Cicchitelli G, Mele D, Fucili A, Ceconi C, New York Academy of Sciences (2004) Therapeutic effects of L-carnitine and propionyl-L-carnitine on cardiovascular diseases: a review
adults affected
Jameson KG, Kazmi SA, Ohara TE, Son C, Yu KB, Mazdeyasnan D, Leshan E, Vuong HE, Paramo J, Lopez-Romero A, Yang L (2025) Select microbial metabolites in the small intestinal lumen regulates vagal activity via receptor-mediated signaling