Recommended Daily Dose of Myo-Inositol
The recommended daily dose of myo-inositol is 4000 mg (4 g) per day, typically divided into two doses of 2000 mg each.
Dosage Recommendations Based on Evidence
The recommended dosage of myo-inositol varies depending on the condition being treated, but the most robust evidence supports a daily dose of 4000 mg (4 g):
Standard dosing: The FDA label indicates one capsule daily or as directed by a healthcare professional 1, but this is a minimum recommendation.
For PCOS and fertility: The most consistent evidence supports 4000 mg daily (2000 mg twice daily) plus 400 μg folic acid (200 μg twice daily) 2, 3. This dosage has demonstrated effectiveness in:
- Restoring ovulation in 70% of women with PCOS
- Achieving pregnancy rates of approximately 15%
- Significantly reducing testosterone levels
- Improving oocyte quality in women undergoing IVF
For psychiatric conditions: Higher doses of 12 g daily have been studied for depression, panic disorder, and obsessive-compulsive disorder 4
For type 2 diabetes: A combination of myo-inositol (1100 mg daily) with d-chiro-inositol (27.6 mg daily) has shown effectiveness in improving glycemic control 5
Safety Profile
Myo-inositol has a favorable safety profile:
Mild side effects: Even at the highest studied dose of 12 g/day, only mild gastrointestinal side effects such as nausea, flatulence, and diarrhea were reported 6
No dose-dependent increase in side effects: The severity of side effects does not increase with dosage 6
No significant changes: No clinically relevant changes in hematology, kidney, or liver function have been reported with myo-inositol supplementation 4
Special Considerations
Pregnancy: Myo-inositol has been studied for its potential role in preventing neural tube defects, especially in folate-resistant cases 7. However, more research is needed before making specific recommendations for this purpose.
Timing: For women with PCOS planning pregnancy, the typical duration of treatment is 2-3 months before attempting conception 2, 3
Combination therapy: Myo-inositol is often combined with folic acid (400 μg daily) for reproductive health applications 2, 3
Conclusion
For most applications, particularly PCOS and fertility concerns, a daily dose of 4000 mg (4 g) of myo-inositol, typically divided into two doses of 2000 mg each, represents the most evidence-based recommendation. Higher doses up to 12 g daily may be considered for certain psychiatric conditions but should be implemented under medical supervision.