5htp is a neurotransmitter precursor so could possibly alter brain chemistry. Not all OTC supplements are going to do this. Seems Rx meds pose a similar danger.

Could consider supplementing with basic nutrients that function more globally and are known to be vital to brain function - B vitamins, vit D, magnesium, zinc, essential fatty acids. Plus the usual good sleep, sunshine, exercise,

Also unaddressed hypothyroid and hypoadrenals can be ruinous to mood, energy, etc.