vitacost synergy acetyl l carnitine alpha lipoic acid & coq10 Nature's Lab® - + + L-Carnitine HCL - 60 Capsules Vitacost CoQ10 Heart Health Support

What is their recommended dosage and frequency based on their age

Vitamin C IV Hydration & IM Vitamin C Injection Rejuvenate your body by speeding up recovery, boosting energy, and improving resiliency to infections

10.1038/s41598-017-06021-5 66 LiH.ZhaoC.TianY.LuJ.ZhangG.LiangS.et al (2020)

An irreversible inhibitor of 17-hydroxysteroid dehydrogenase type 1 inhibits estradiol synthesis in human endometriosis lesions and induces regression of the non-human primate endometriosis

That said, L-citrulline supplements are still a viable option, particularly if budget is a primary concern

The role of NAD + in immunomodulation is context and signaling pathway specific