Is it safe to continue my dose of levothyroxine and begin taking garcinia cambogia to lose weight?

It is probably safe: ...but it may not be very effective. Garcinia cambogia is a tropical fruit, the Malabar tamarind. It is touted to block fat metabolism and may naturally raise serotonin making you feel less hungry. I doubt it has any special negative effects in those taking thyroid supplements. But it's actual weight loss results aren't impressive. I would probably save my money. Good wishes:)