30-year old Chandrasekaran, a lorry driver, and his wife Sumati of Podanur had been undergoing treatment for AIDS for the past couple of months, they said.
Dejected over their plight, the couple consumed poisonous cow dung powder last evening, they said.
Neighbours, who found the two unconscious, rushed them to the government hospital here, but the woman died on the way, police said adding the man was undergoing treatment and his condition was stated to be critical.