So my friend has a pint of the wockhardt promethazine syrup plain NO codeine. Can my friend still pour up a 4 like you normally do with lean and will it give you any effect?
I'm not sure what a 4 is... but promethazine is psychoactive, yes. It will make you drowsy but doesn't really get you high on it's own... I wouldn't recommend trying to get high on promethazine.
4 fl oz of liquid. Being nearly 120mL, with normal lean it equals 240mg of codeine. A pretty solid dose.
Plain promethazine syrup isn't going to get you high. It's just an antihistamine. Save the syrup to potentiate other opioids or sell it to someone for the goofy inflated prices people will pay to look cool.