A young child was taken to hospital earlier this month after being found at a Bay of Plenty motel where P was allegedly being smoked.
Senior Sergeant Mark Pakes said police went to the motel after receiving information from a member of the public.
Police made three arrests and took a 19-month-old to the hospital.
Police later referred the child to welfare services.
Police charged a 24-year-old woman with allowing premises to be used to use methamphetamine, Mr Pakes said.
A 47-year-old man was arrested in connection with outstanding warrants and charged with possession of methamphetamine for supply, possession of methamphetamine utensils and possession of cannabis utensils.
A 27-year-old woman was charged with being in possession of methamphetamine and utensils.
Mr Pakes said he was limited in what he could say while the matter was before the courts.