Exposing the truth about painkillers: The warnings and solutions
For example, phenylalanine helps to restore enkephalins and endorphins, deficiencies of which can trigger the abuse of opiate painkillers – as well as of sweets, starches and nicotine. Both phenylalanine and the amino acid tyrosine also help to restore dopamine and norepinephrine – shortages of which can lead to cravings for stimulants such as caffeine, cocaine and amphetamines
