The best thing to do is start with probacto probiotics and some dietary changes. I also recommend you checkout this video on youtube, this guy shares some great tips.
If you been on antibiotics for this long then you will have to take probiotics for at least 5-6 months as well and make sure you incorporate some changes in your diet as well check Sean's article on probacto's blog.
Another thing to know is that probiotics manufactured by companies with no knowledge of probiotics is usually useless. 20 billion live cultures is useless if it is not meant for candida overgrowth. Further, the bacterias in these supplements never pass the stomach acid wall. Probacto probiotic has special armor coating that passes the stomach acid and makes sure you get maximum delivery.
Let me know if you have any further questions.