Hi there. This DIYer did it without chemicals if you want to check it out. https://www.hometalk.com/39275336/how-to-clear-a-clogged-sink-drain-without-chemicals
Hi Sam there is always the good old plunger or drain snake.
or the snake
pour coca cola in drain, wait 5 min. and pour boiling water in drain. repeat boiling water 2 or 3 times. If this doesn't clear it, try snake.
A snake will clear a clog if it is within reach. If that and draino don't clear it, you may have to call a plumber. They have the tools to clear something further down the line.