PHILADELPHIA (CBS) – Drinking plenty of fluids may not necessarily be the right move when battling an illness, medical researchers say.

According to CBS News, an article published in BMJ Case Reports describes the case of a 59-year-old woman who developed hyponatraemia — a condition that occurs when the level of sodium in the body is abnormally low — from drinking too much water to help with a recurring UTI.

Dr. Maryann Noronha, a senior author of the report, tells CBS News, “The effect of illness on the body as well as people’s natural tendency to stop eating and drinking when unwell combine to make the risk of dehydration during illness a real concern.”

“To counteract this, medical advice has always been to ensure to stay well hydrated during periods of illness,” she said. “On the whole this advice is followed within reasonable limits. However, if taken to extremes, as in this case, the consequences can be as serious as that of not consuming enough water.”

The patient was reportedly admitted to the ER and prescribed medication for her infection. Soon her health started to deteriorate. She became shaky, muddled and vomited several times.

CBS News says tests showed her sodium levels were dangerously low, a result of water intoxication.

Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City, tells CBS News that case report highlights the importance of not consuming excessive amounts of water to try to clear a routine urinary tract infection.

“The old adage to ‘drink plenty of water’ should be approached with caution if you are not vomiting, or experiencing diarrhea, or excessive sweating,” he advises.

“In general, the average person should not be overly concerned about over-hydrating,” Glatter tells CBS News.

“Drinking one to two or even up to three to four extra glasses of water per day for the average person with normal kidney function and in otherwise good health is not a concern.”

“However, if you are the type of person who excessively increases the amount of water you consume during a period of illness (i.e. doubles or triples), it maybe it is something to bear in mind if you start developing unusual symptoms such as a headache or slurring of your words.”