Go check with the SOS clinic - I don't know where it is located, but there is one in HCMC. If youare not yet in Viet Nam, medicines may be less expensive where ever you are coming from than in VN, and not all medicines are available locally.
Brown rice is sold in Ha Noi, so my guess is it must be sold in HCMC.
The biggest problem with medicines in VietNam is ensuring that they are (1) real - and not a Thai / Chinese knock off and (2) fresh.
Medications are available from pharmacies, some simply open a draw and invite you to pick your winner. I have even seen Demerol tablets available in one of these places.
I would bring a 3-month supply with you (and a photocopy of the prescription along with them) so you have time to organise your local source.
Tampons are now available in Western-style supermarkets (in the larger towns up and down the country) as are many other Western supplies but you will have to pay for the luxury. Ditto with 'supplements'.
If you wear contacts bring along a three-month supply of whatever you need until you determine where the local sources are.
VietNam rice enjoys a great reputation in the world and is much sought after. But it is white.
The SOS clinic, as well as many other very competent clinics are available in HCMC, Da Nang and Ha Noi. There is a large hospital in District 5/6 where modern Western-style medical services are available at a price.
As for dentists there is the Canadian-standard < www.maplehealthcare.net/english/index.php >that boasts equipment more modern than my dentist in Canada.