A Lutselk'e, N.W.T., man is demanding compensation from Shoppers Drug Mart after a pharmacist at its Yellowknife store gave him pills that were 10 times the dose he was prescribed.

James Marlowe says he was prescribed 12.5 mg of a medication called metoprolol to be taken twice daily for high blood pressure in May 2016.

After the prescription was faxed from his doctor to the Shoppers Drug Mart pharmacy in Yellowknife, Marlowe was given a bottle of pills.

He says he took the pills for a month but began feeling negative side effects.

'I felt dizzy'

"At the time, when I was taking that medication, I felt dizzy. When I was climbing the stairs, working at the diamond mines, at times I was tired and dizzy," Marlowe told CBC.

"I didn't know that dizziness and tiredness were side effects of the medication because it was slowing my heart rate down."

Marlowe says it wasn't until he saw a nurse in his home community of Lutselk'e that he discovered he was actually taking 125 mg twice a day instead of the 12.5 mg he was prescribed —10 times his doctor's recommended dose.

​"It was fortunate my heart didn't stop," Marlowe said.

"I saw a specialist in Edmonton and he was surprised that nothing happened to me in regards to the high dosage of medication that was given to me. I was fortunate."

"We apologize:" Shoppers offered Marlowe a gift card after he told them about the mistake. (Eduardo Lima/Canadian Press)

Marlowe says he called the Yellowknife Shoppers Drug Mart pharmacy but was given a number for the company's head office in Toronto. When he described the situation to a representative on the telephone, he says they offered him a $100 Shoppers Drug Mart gift card for their mistake.

"I thought that was despicable," Marlowe said.

"That was a big slap in the face for me."

CBC News contacted Shoppers Drug Mart about Marlowe's situation.

"This type of situation is very rare"

"This is a serious matter and we apologize for the error on behalf of the pharmacy team. Each Shoppers Drug Mart pharmacy has rigorous professional standards for providing excellent patient care," Tammy Smitham, Shoppers vice president of external communications, responded in an email.

"This type of situation is very rare. We have investigated this incident and have followed up with the pharmacy team directly."

Smitham later said the error stemmed from the faxed prescription in which "the decimal was not apparent."

Marlowe is now asking for more than $50,000 in compensation to cover his family's living expenses for a year.

He wrote in an email to the company that this amount is based on what he thinks his family "would require to live day-to -day, should I have passed on due to the medication given to me by Shoppers Drug Mart."

Marlowe says Shoppers Drug Mart has yet to respond to his request.