I have had candida problems for many years (headaches, sinus problems, constipation, tiredness).
I previously tried threelac which in my case didnt seem to make much difference. Then I tried samento which helped a bit. Finally I tried Fivelac, since when I have noticed quite a lot of improvement in all my symptoms.
What has been great is that I now seem to be able to get away with sweet food in moderation whereas before it caused headaches and sinus problems within a couple of hours.