Falador Apothecary
The Falador Apothecary is a minor character in the first RuneScape novel, Betrayal at Falador. The Apothecary sold the White Knight peon Bryant guam leaf and nightshade. Bryant was unaware that he was being used to obtain materials for Sir Finistere to create a poison.
As he does not appear in-game, it is likely the Apothecary has since passed away or retired.