Safety Profile
Overall safety rating: Generally Safe
I3C (Indole-3-Carbinol) Side Effects & Safety
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Potential Side Effects
- GI discomfort (nausea, bloating, gas) — more common than with DIM
- Skin rash in sensitive individuals
- Dizziness at higher doses
- Equilibrium-related side effects reported at 800mg+ doses
Drug & Supplement Interactions
- May reduce efficacy of estrogen-based medications and contraceptives
- Induces CYP1A2 — may increase metabolism of caffeine, theophylline, and certain drugs
- May interact with tamoxifen and other hormone therapies
Maximum Dose
Do not exceed: 400mg daily (higher doses increase GI side effects)
References
- Bell MC, Crowley-Nowick P, Bradlow HL, Sepkovic DW, Schmidt-Grimminger D, Howell P, Mayeaux EJ, Tucker A, Turbat-Herrera EA, Mathis JM (2000). Placebo-controlled trial of indole-3-carbinol in the treatment of CIN. Gynecologic Oncology. DOI PubMed
- Reed GA, Arneson DW, Putnam WC, Smith HJ, Gray JC, Sullivan DK, Mayo MS, Crowell JA, Hurwitz A (2005). Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmethane. Cancer Epidemiology, Biomarkers & Prevention. DOI PubMed