Riboflavin 5'-Phosphate 36.5 mg by Thorne

Choose this if you want active B2 without relying on your gut and liver to convert it. It fits plant‑based eaters, low‑calorie or restrictive dieters, and anyone with digestive or liver issues where vitamin activation can lag. It’s useful if your Homocysteine (an amino acid that rises when methylation is sluggish) stays high despite folate and B12, or if you get recurrent mouth corner cracks. For migraine prevention, most protocols use far higher riboflavin than this maintenance‑level dose.

Riboflavin 5'-phosphate is FMN, the tissue‑ready form your cells use to make FAD, both of which power enzymes that turn carbs and fats into ATP energy. This form also helps “activate” other vitamins: it’s required to convert B6 and folate into their working forms and to recycle glutathione (the cell’s main antioxidant). That’s why improving riboflavin status can nudge Homocysteine down in some people and steady energy production within weeks.

Take one capsule daily with food, which improves absorption and is gentler on the stomach. Morning works well for most, but timing isn’t critical. This is a maintenance dose; repletion for clearly low B2 or migraine prevention typically uses much higher amounts guided by a clinician. Expect bright yellow urine—just riboflavin’s color, not dehydration.

Separate riboflavin from tetracycline antibiotics by 2–4 hours to avoid reducing the antibiotic’s absorption. Alcohol intake increases B‑vitamin needs, so consistency matters if you drink. Pregnancy and breastfeeding: riboflavin is essential and commonly used in prenatal vitamins, but check your total B‑complex intake to avoid stacking high doses.