I've been taking berberine off and on since last September (2014). It was the missing piece in my natural skin healing journey that has helped me stay 95% - 99% clear (finally!!).
*Disclaimer: I am not a health professional. These answers are based on my experience and are not meant to replace the advice of your doctor. Please consult with your physician or naturopath prior to starting any supplement to see if it's a good fit for you.
What is berberine?
Berberine isn't really a herb - it's an alkaloid compound that is isolated from plants such as Barberry, Goldenseal and Oregon Grape. It's been used in traditional Chinese medicine going back centuries and is currently making a resurgence as an herbal treatment for type-II diabetes, poly cystic ovarian syndrome, high cholesterol and acne. To learn more about berberine, read my post here.
What brand should I take? Where can I buy it?
My naturopath carries Throne Research Berberine, so that is the only brand I have experience with. Overall, Thorne Research is a reputable brand with high quality products that I've been very happy with. The brand isn't carried in stores and it can't be directly ordered through their website without an affiliation with a naturopath/doctor (I think it's a business to business marketing set-up). However, you can order it through various online stores like Amazon.
I have noticed lately that a few health stores in my city carry Dr. Whitaker's Berberine, so that may be an option if you want to pick it up locally. I'm not sure of the quality, but it has generally good reviews on Amazon.
How long can I take berberine for?
This is where it gets a little iffy. My naturopath didn't seem too concerned with long term use when I asked her about it, but hormone health blogger and ND Dr. Lara Briden suggests taking breaks and not using the herb for sustained amounts of time as the anti-microbial effects of berberine may not be healthy in the long run for your gut. Always take a good quality probiotic/eat fermented foods when you're taking berberine and following your berberine course.Dr. Briden recommends in her Love Vitamin post to take a break one day a week, and take a month break following a three month course. Lately I've been taking berberine for the first two weeks of my cycle, followed by a two week break. My skin sometimes gets a couple pimples during the two week break, but overall stays fairly clear.
What dosage should I take?
Follow the directions on the label or from your naturopath. I take one 500 mg Thorne Research Berberine tablet twice daily. My naturopath initally prescribed 1,000 mg twice daily which was too much for my system. After about a week at this dosage, I started feeling quite ill. You may want to start with one tablet per day for a few days to see how you tolerate the compound and then work up from there.
How long do I have to wait to see results?
This would vary depending on the person. One study showed a 45% improvement in acne following four weeks at 600 mg of berberine/barberry extract daily. The study group was 12 - 17 year olds. This is only one clinical trial, but those are fairly promising results. The dosage wasn't very high either.
Personally, I saw a slight improvement of my acne following a few weeks on 2,000 mg daily. My skin cleared 100% when I took 500 mg twice daily of berberine for a couple months and combined that with a three month gluten-free, sugar-free and processed food-free diet to help heal my gut and any insulin resistance. Berberine is excellent for helping your body overcome insulin resistance. My skin has remained clear even though my diet isn't as strict anymore and I'm not taking berberine daily.
Who shouldn't take berberine? Can I take it if I'm pregnant/planning on getting pregnant/breastfeeding?
Do not take berberine if you are pregnant or breastfeeding as it has been shown to cause severe jaundice in infants and can lead to brain damage. If you are trying to conceive, only take berberine for the first two weeks of your cycle.
If you are breastfeeding, a good anti-fungal supplement that is safe is Thorne Research Formula SF722. I took this almost daily for nine months (November 2013 - August 2014) and found it cut inflammation tremendously and helped me get through multiple candida cleanse challenges. It isn't as powerful an anti-microbial as berberine, but it's a good start. It may even be safe to take while pregnant, but you'd have to check with your naturopath on that one.