They can't make your energy, and you're going to feel tired
Frequently asked questions Can I just take an oral B12 supplement with my regular semaglutide
You can use peptides for months or years safely while traditional pain medications cause cumulative damage
For people with cobalt allergy (which is more common among people with nickel allergy) who are also at risk of vitamin B12 deficiency, the "general advice seems to be 'take just enough but not too much,' which isn't too different from dosing advice for all vitamins and drugs" (via ACSH)

Seek medical advice if you experience: New-onset insomnia or significant sleep disruption that persists after starting B12 supplementation Paradoxical fatigue : Worsening tiredness despite taking B12, which may indicate an underlying condition requiring investigation Neurological symptoms : Tingling, numbness, balance problems, or cognitive changes, which could suggest B12 deficiency or other neurological conditions Mood changes : Anxiety, agitation, or depression that develops or worsens after starting supplementation Palpitations or rapid heartbeat : Though rare, some individuals report cardiovascular symptoms that should be evaluated It's important to note that sleep disturbances may be unrelated to B12 supplementation
J Stroke Cerebrovasc Dis 13:129137