In this warm weather, it is NEVER ok to leave a dog in a vehicle. At the Groove Festival in Bray last weekend, a dog had to be removed from the back of a van by the police after it was found to have been left there. Listen to this podcast to find out more about why dogs cannot be left alone in cars in the summer.
Please note that I am unable to answer veterinary questions in comments. If you have questions or concerns about your pet's health it is always better to contact your vet.