The Albion captain angered visiting supporters during Wednesday morning's (AEDT) 1-1 draw at The Hawthorns when he appealed for a corner while Swansea midfielder Ki Sung-yueng lay on the ground with a head injury, prompting chants of "what's it like to s*** your pants?" in reference to Fletcher's successful battle against ulcerative colitis.
Fletcher, 32, underwent surgery for the debilitating illness three years ago and since signing for West Brom has become Pulis' most important player.
Unbeknown to Fletcher as he appealed for the corner, the referee had stopped play so that Ki could receive treatment following a clash of heads with Stephane Sessegnon. The South Korean was carried off on a stretcher with what turned out to be a minor concussion.
After the match Fletcher described the chanting as "a bit of stick" and conceded that it was "part and parcel of the game", and his manager was similarly unmoved by it.
"That's all it was, it is part of the game," said Pulis, whose side face Newcastle on Saturday.
"I'm not really convinced it's anything more than banter. Supporters pay enormous amounts of money now to come and watch football and they have the right to say what they want and do what they want.
"Darren is big enough and old enough to take that on the chin and get on with it."
And Pulis suggested that Fletcher would need to develop a thick skin should he pursue his ambition of moving into management.
He added: "The lad wants to go into coaching and management and I think eventually become a very good manager. So he'll have to get used to taking a bit of stick."
The West Brom players, and Pulis, were also on the receiving end from their own fans, as they voiced some discontent on Wednesday morning.
Albion were booed at full-time for the second successive home Barclays Premier League game, despite Salomon Rondon's injury-time equaliser salvaging a precious point in the battle against relegation.
But Pulis insists he and his team have the backing of most of the fans and that was just a minority of supporters.
"There was a little bit of booing - but 99.9 per cent of supporters were absolutely delighted we scored a late goal and they showed their appreciation," said the Baggies boss.
"What happens is you get one or two people booing and then everyone gets tarnished with the fact the supporters were booing.
"The supporters weren't booing, they stuck with us until the end. If you watched the last 10 minutes of that game - the support the players got from our fans was fantastic.
"Some people do get frustrated and so you'll get one or two boos and you have to accept that."
West Brom were dealt another injury blow ahead of their trip to St James' Park with the loss of Jonny Evans.
Evans limped off against Swansea with a hamstring problem and the defender will be out for at least a couple of weeks. The Northern Ireland international joins compatriot Chris Brunt (calf), James Morrison (hamstring) and Callum McManaman (ankle) on the sidelines.
Saido Berahino will be in the squad against the club who had a bid for him rejected before the transfer deadline, although Pulis says the striker is unlikely to start as he continues to build up his fitness.