At the time of 35-year-old Lynsay Jackson's death last year it was thought she had died from a heart attack. However, following the outcome of toxicology tests her death certificate has been updated, showing that she died from a Propranolol overdose.
The drug, technically known as a beta-blocker, is prescribed for a variety of common health problems including high blood pressure, angina, irregular heartbeat, anxiety and thyroid problems.
It is also used as a treatment for other ailments including migraine headaches and glaucoma.
Mrs Jackson, whose baby daughter Emilie was just 10 months old at the time of her death, was thought to have suffered cardiac failure at her home in Crossmichael, Kirkcudbrightshire, in the early hours of the morning after going to bed complaining of stomach pains.
Medical experts said Propranolol was usually a safe drug but that care should be taken to ensure the correct dose is taken. It is known to slow down the heart, which can result in the patient feeling weak.