It can be safe if monitored by a qualified doctor who checks dosage, frequency, and overall health.
There have been no large-scale, long-term studies to truly evaluate safety especially not for cancer risk
Sirolimus-induced anemia is associated with low mean corpuscular volume (MCV), microcytosis
12 Although these compounds are beneficial in the free form, it was also confirmed that when bound to lens proteins, as occurs with increasing age in the lens nucleus, these UV filters become stronger photosensitizers which can, in the presence of oxygen and UV radiation, generate singlet oxygen, superoxide anion, and hydrogen peroxide within the lens nucleus 24 Hydrogen peroxide, although producing little direct damage, can be converted into highly reactive and damaging species in the presence of transition metals
Larger peptides and those without specific transport mechanisms may have limited BBB penetration, which is why administration route matters so much for neurological applications
Effect of two paradigms of chronic intermittent hypoxia on carotid body sensory activity