l-glutathione supplements Healthy Origins® (Setria®) 500mg "reduced" Luma Nutrition Premium Glutathione Supplement

Or if you have a mild headache you can turn to over-the-counter pills

It is important to approach the claimed benefits of glutathione injections with nuance

Since DmGSTS1-1 was highly expressed in the flight muscle, the localization of the corresponding GST enzyme might provide a protective role against oxidative stress generated from mitochondrial respiration [128]

Note: This article summarizes dosage ranges used in animal research, preclinical models, and community discussions

So in theory, the free copper is definitely a potent 5AR inhibitor and if free copper concentrations reach a decent level in the scalp, you can expect a big inhibition of local 5AR1