Allergic Reactions (Rare): Although rare, some individuals can have an allergic reaction to the injection, ranging from a rash or itching to more severe symptoms like swelling of the face, tongue, or throat, dizziness, or difficulty breathing
Your body produces it on its own, but production declines significantly with age, from roughly 200 ng/mL at age 20 to around 80 ng/mL by age 60
PMID: 16244184
Wu Q, Wang X, Nepovimova E, Wang Y, Yang H, Kuca K (2018) Mechanism of cyclosporine A nephrotoxicity: oxidative stress, autophagy, and signalings
It has also been shown that AgNPs can enter the central nervous system directly via the olfactory or trigeminal nerves[123]