Yeast infection can be caused by a number of things, like:
Antibiotics; the antibiotic kills the unwanted bacteria in your sinuses, but can also kill the "good" bacteria in your vagina, upsetting the balance of your vaginal ecosystem, allowing the yeast to take over. (Antibacterial deodorant soap can have the same effect.)
Clothing: vaginal yeasties flourish in non-cotton, tight, or dirty clothes that trap heat and moisture.
Condoms can promote yeast infections in two different ways. First, a lot of condoms come packaged with a lubricant that contains nonoxynol-9. Several recent studies have shown that nonoxynol-9 is linked to yeast infections. Condoms can also cause yeast infections if you are allergic to latex, although this is less common. if this is the case, don't give up hope on practicing safer sex.
Hormones, both naturally-occurring and artificially introduced, can affect yeast.
Like your doctor suggested, eat diary products (i find yoghurt more effective) twice to three times daily. It also works when applied topically. Insert some into the vagina using a finger or plastic tampon applicator. Use only plain yogurt with active cultures.
Decrease or eliminate sugar and sugary foods. Sugar promotes yeast growth.
Garlic is a natural antibiotic and antifungal. You can consume garlic in food or take it in pill.
Honey is probably the most sticky and uncomfortable way of curing vaginal yeast infection, but it is said to work wonders. Take half a cup of honey into the bathroom. Pour a liberal amount of honey on all affected portions, while sitting on the toilet seat. Be seated this way for about 20 minutes. After this you can have a bath with warm water. Dry the vaginal area thoroughly using super absorbent paper. You will feel much better. Do this twice a day, morning and just before going to bed at night.
Dry vaginal area throughly after showering or swimming. A moist environment encourages the growth of yeast. Avoid wearing tight clothing such as tight jeans, nylon panties, pantyhose, or clothing made of synthetic materials such as polyester. A tight, moist environment encourages the growth of yeast.
Wipe yourself after urinating or a bowel movement from front to back. This helps to avoid possible transfer of yeast from the rectum to the vagina. Avoid use of feminine hygiene products such as feminine sprays and bubble baths. These products can be irritating to the vagina.
Use unscented pads and tampons during your menstrual period.
I hope i'v been of any help. Good luck!