Neurological: convulsions, increased intracranial pressure with papilledema (pseudotumor cerebri) usually after treatment, vertigo, headache Endocrine: menstrual irregularities, development of cushingoid state, suppression of fetal intrauterine or childhood growth, lack of secondary response of the adrenal cortex or pituitary gland, particularly in situations of stress such as trauma, surgery or illness, decreased carbohydrate tolerance, manifestations of latent diabetes mellitus, increased requirements of insulin or oral hypoglycemic agents in diabetic patients Ophtalmic: posterior subcapsular cataracts, increased intraocular pressure, glaucoma, exophthalmos Metabolic: negative nitrogen balance due to protein catabolism Psychiatric: euphoria, mood swings, severe depression to frank psychotic manifestations, personality changes, hyperirritability, insomnia Others: anaphylactoid or hypertensive reactions and hypotension or shock-like reaction Cyanocobalamin and hydroxocobalamin: hypervitaminosis and side effects were not observed with their use Dosage and administration Adults Coated tablets: 1 coated tablet 2 times a day

Here are some potential ways B-complex vitamins might indirectly influence performance: Energy Production : B-complex vitamins play critical roles in energy metabolism, helping convert carbohydrates, fats, and proteins into usable energy
This reaction effectively diverts nicotinamide away from the NAD+ salvage pathway, reducing the cell's capacity to regenerate NAD+
Some patients receiving Vitamin B12 injections report feeling worse after their treatment, an unexpected reaction considering these injections are typically used to alleviate symptoms of B12 deficiency
Emerging paramyxoviruses: receptor tropism and zoonotic potential