Excess melanin stimulating hormone is secreted in?

Parkinson disease

Alzheimer disease

Addison disease

Both b and c

Excess melanin-stimulating hormone (MSH) is secreted in Addison's disease

Because the adrenal glands are not producing enough cortisol

Which leads to an increase in ACTH (adrenocorticotropic hormone)

Which in turn stimulates the production of MSH, resulting in hyperpigmentation (darkened skin).