Sherman Lai was first charged with sexual assault against a former patient in October.
In total, 13 charges have been laid against the 58 year old after 11 former patients brought allegations of sexual assault to police.
“We believe there’s likely going to be more victims out there and we’re hoping they’re willing to come forward,” said Const. Mike Gatto.
In addition to the latest sexual assault charges laid on Friday, Lai was also charged with assault with a weapon and uttering death threats.
Guelph police said Lai practised at the Centre of Integrative Natural Medicine on Surrey Street for over 20 years and moved his practice to nearby Morriston about six years ago.
Guelph police are reminding the public that there is no statute of limitations on crimes of this nature.
Anyone with information can call Guelph police at 519-824-1212 ext. 7518 or Crime Stoppers at 1-800-222-8477.