There are plenty of health care professionals who give poor advice because they aren't aware that it is bad advice. I would let your GP know that the pharmacist gave you a list of a number of safe medications like traveller suggested and see how they respond.
I had a pharmacist tell me that the only option for drops for my non-closing eye when I got Bell's Palsy was Visene which specifically says not to use when breastfeeding. A GP was also at a loss when asked, but within about 30 seconds my ob gave me a list of a dozen safe options off some database he had access to. Maybe GPs need to be reskilled at using drug databases? I don't really expect them to know everything, but I do expect them to take a patient's requests seriously and to be able to find the answer when they need to.