Provillus is a supplement / topical formula combination that is sold over the internet for treating hair loss in men and women. Provillus now contains minoxidil, which is an FDA approved hair loss drug that is also sold over the counter as Rogaine and various store-brand solutions. Provillus side effects are the same as those that can be experienced with any hair loss formula containing minoxidil. 
Most people do not experience side effects, but some may notice irritation of the scalp. A few users of Provillus have reported a sensation of a racing heartbeat, which may be due to one of the ingredients in the nutritional supplement that comes with the topical solution. Saw palmetto (1,000 mg) is contained in the supplement, and this has been known to rarely result in a sensation of heart racing, which may be more noticeable for those who take drugs called beta blockers.
So what happens when you buy Provillus? The topical preparation and nutritional supplements arrive with minimal instructions, but the supplements are taken 2 at a time, and the solution is applied to the scalp the way you would apply any formulation of minoxidil. Minoxidil has been shown to regrow hair in people whose hair is thinning as long as it is used consistently. It may take up to 6 months for the effect to be noticeable, and hair loss resumes as soon as the treatment is stopped.
The nutritional supplement is a blend of herbal, vitamin, and mineral products that include Vitamin B6, Mura Puma Root, Pumpkin Seed Meal, Siberian Ginseng, Zinc Sulfate, Nettles, magnesium, Gotu Kola, and Saw Palmetto. As mentioned above, saw palmetto has been known to cause heart palpitations in a small percentage of users.
A number of online forums discuss whether Provillus is a scam. Whether Provillus was effective in formulations before they started adding minoxidil is open to debate. Now that the topical part of Provillus contains minoxidil, it can legitimately claim to regrow hair, because the FDA has approved minoxidil for that purpose. There is some question as to whether the nutritional supplements help. Some users say that it does, and some say that it does not.
Satisfaction with Provillus generally depends upon whether the user likes Provillus' exact formulation of the topical solution. This may come down to personal preference. Generally speaking, it should work about as well as any minoxidil formulation with the same drug concentration (5% in the men's version)