This phenomenon, sometimes referred to as early worsening of diabetic retinopathy, appears to be related to the magnitude and speed of glucose lowering rather than a direct effect of the medication
Critical Reviews in Clinical Laboratory Sciences
Presented for research literature review only CALAM DH et al
Addressing this concern, Hyderabad-based neurologist Dr Sudhir Kumar took to Twitter to note that while vitamin B12 deficiency is known to cause anaemia, peripheral neuropathy, dementia, psychosis and skin pigmentation, calling for supplementation, excessive vitaminB12 may have adverse effects on health and life. Excess of vitamin B12 may be hazardous 1
That means no increase in IGF-1 production, no effect on blood glucose, no insulin resistance, no water retention, and no risk of the organ growth associated with full HGH therapy
Davies (ed.), A Case-Based Guide to Clinical Endocrinology, 2008, pag.16 "Effect of Growth Hormone on Insulin Signaling"