What are they?

Anthocyanidins are nutritional supplements. They have strong antioxidant properties that can, in theory, support and prevent the destruction of collagen in muscles.

The effectiveness of anthocyanidins for fibromyalgia was only tested in one small RCT. No reduction in pain and an unconfirmed improvement in fatigue and sleeping problems were found. Because the data is limited, we can’t yet give a reliable evaluation of the role of this treatment for fibromyalgia.

  • Family: Nutritional supplement
  • Scientific name: Anthocyanidins
  • Other names: Colladeen®

Anthocyanidins are a subgroup of flavonoids, which are chemicals that are made from the parts of some plants that don’t provide nutrients. You can buy anthocyandins capsules (Colladeen®) over the counter in pharmacies or over the internet.

How do they work?

Several laboratory studies have shown that anthocyanidins can act as strong antioxidants. Anthocyanidins can also prevent the destruction of collagen in the muscles, a problem that has been observed in some people with fibromyalgia.

Are they safe?

Reported side-effects on short-term usage include:

  • stomach upsets
  • rashes
  • problems passing urine.

There are no reports on the long-term safety of anthocyanidins and interactions with other drugs haven’t been well studied.

Doses ranging from 40–120 mg a day have been used in an RCT. No trials have been conducted to find the best dosage in musculoskeletal conditions.

Anthocyanidins trials for fibromyalgia

A small trial of 12 participants evaluated the role of anthocyanidins in treating fibromyalgia. Participants were given one of the following once a day for three months:

  • 40 mg of anthocyanidins
  • 80 mg of anthocyanidins
  • 120 mg of antocyanidins
  • placebo tablets.

Participants were asked to report the severity of their pain, the degree of fatigue and sleep problems in a daily diary. The investigator also evaluated the improvement of these symptoms by interviewing the participants once every month.

  • Anthocyanidins weren’t effective in reducing pain (as evaluated by the participant and the investigator) at any daily doses during any part of the follow-up.
  • Participants reported a similar lack of effect on fatigue, although the investigators observed some beneficial effect during the interviews.
  • A significant reduction in sleep disturbance was reported in the daily reports of participants taking anthocyanidins compared to those on the placebo, but such beneficial effects weren’t confirmed by the investigators during interviews.
  • Participants who were on anthocyanidins reported more side-effects than those who were given placebo capsules.