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Inositol is part of the vitamin B-complex. It is required for proper formation of cell membranes. 

What Are Star Ratings?

This supplement has been used in connection with the following health conditions:

Used for Why
2 Stars
4 to 6 grams three times per day
Inositol has been used to help people with anxiety who have panic attacks.

has been used to help people with anxiety who have panic attacks. Up to 4 grams three times per day was reported to control such attacks in a double-blind trial. Inositol (18 grams per day) has also been shown in a double-blind trial to be effective at relieving the symptoms of obsessive-compulsive disorder.

2 Stars
12 grams of inositol daily
People with depression may have lower levels of inositol. Supplementing with this nutrient may correct a deficiency and improve depression symptoms.

Preliminary evidence indicates that people with depression may have lower levels of . Supplementation with large amounts of inositol can increase the body’s stores by as much as 70%. In a double-blind trial, depressed people who received 12 grams of inositol per day for four weeks had a significant improvement in symptoms compared to those who took placebo. In a double-blind follow-up to this trial, the antidepressant effects of inositol were replicated. Half of those who responded to inositol supplementation relapsed rapidly when inositol was discontinued.

1 Star
Bipolar Disorder
Refer to label instructions
Inositol may be useful for treating depression in people with bipolar disorder.

is a nutrient found in large amounts in the brain, but its possible role in mood disorders is unclear. Inositol levels may be reduced in certain parts of the brains of depressed and bipolar patients. However, lithium reduces normal brain levels of inositol, and this may be one of the ways lithium helps people with bipolar disorder. Although inositol is known to have significant antidepressant properties when administered in large amounts of 12 grams per day, case reports involving bipolar patients have reported either no benefit, some benefit, or worsening of symptoms from inositol supplementation. Until controlled research clarifies the effects of inositol in people with bipolar illness, it should only be used under the supervision of a qualified healthcare practitioner.

1 Star
Type 1 Diabetes
Refer to label instructions
Supplementing with inositol may improve diabetic neuropathy.
Inositol, particularly in the forms myo-inositol and D-chiro-inositol, has many functions in the body, including assisting in normal cellular responsiveness to insulin. A gene alteration that affects inositol metabolism may be associated with risk of type 1 diabetes and its complications, and people with type 1 and type 2 diabetes have been found to lose more myo-inositol in their urine compared to those without diabetes. In one small pilot trial in seven people with type 1 diabetes, inositol supplementation (500 mg taken twice per day for two weeks) led to improved nerve function; however, two placebo-controlled trials failed to find a benefit.
1 Star
Type 2 Diabetes
500 to 2,000 mg daily
Inositol has been shown to improve glucose metabolism and insulin sensitivity in women with polycystic ovarian syndrome, and preliminary evidence suggests it may lower HbA1c in people with type 2 diabetes.
Disturbances in inositol metabolism are thought to be an underlying factor in insulin resistance and type 2 diabetes. Animal studies suggest inositol may reduce glucose absorption in the digestive tract and have insulin-like effects, increasing glucose uptake and utilization by cells. A pilot trial examined the effects of adding inositol in people with type 2 diabetes with persistently high HbA1c despite medical treatment. A supplement providing two types of inositol (550 mg of myo-inositol and 13.8 mg of D-chiro inositol per day) was added to their treatment. After three months, fasting blood glucose levels and HbA1c had decreased significantly. Reviews of clinical research have shown that inositol can improve glucose metabolism and insulin sensitivity in women with polycystic ovarian syndrome (PCOS), a condition marked by hormonal imbalance and increased risk of insulin resistance, type 2 diabetes, and cardiovascular disease.

How It Works

How to Use It

Most people do not need to take inositol. In addition, the small amounts commonly found in multivitamin supplements are probably unnecessary and ineffective. Doctors sometimes suggest 500 mg twice per day. For depression, anxiety, and obsessive-compulsive disorder, 12–18 grams per day has been shown to be effective in double-blind trials.1, 2, 3, 4

Where to Find It

Nuts, beans, wheat and wheat bran, cantaloupe, and oranges are excellent sources of inositol. Most dietary inositol is in the form of phytate.

Possible Deficiencies

Clear deficiency of inositol has not been reported, although people with diabetes have increased excretion and may benefit from inositol supplementation.


Interactions with Supplements, Foods, & Other Compounds

At the time of writing, there were no well-known supplement or food interactions with this supplement.

Interactions with Medicines

Certain medicines interact with this supplement.

Types of interactions: Beneficial Adverse Check

Replenish Depleted Nutrients

  • Lithium

    Lithium therapy has been shown to deplete brain stores of inositol. While it has been suggested that inositol supplementation (e.g., 500 mg three times daily) could reduce adverse effects of lithium therapy without reducing the drug’s therapeutic effectiveness, the safety and efficacy of this combination has not been proven.

    Treatment with lithium can trigger or worsen psoriasis. In a double-blind study, supplementing with inositol (6 grams per day) for ten weeks significantly improved lithium-induced psoriasis, but had no effect on psoriasis in people who were not taking lithium.

Reduce Side Effects

  • none

Support Medicine

  • none

Reduces Effectiveness

  • none

Potential Negative Interaction

  • none

Explanation Required

  • none

The Drug-Nutrient Interactions table may not include every possible interaction. Taking medicines with meals, on an empty stomach, or with alcohol may influence their effects. For details, refer to the manufacturers’ package information as these are not covered in this table. If you take medications, always discuss the potential risks and benefits of adding a supplement with your doctor or pharmacist.

Side Effects

Side Effects

Toxicity has not been reported, although people with chronic renal failure show elevated levels and should not take inositol, except under medical supervision.

Large amounts of phytate, the common dietary form of inositol, reduce the absorption of calcium, iron, and zinc. However, supplemental inositol does not have this effect.

One review article suggested that inositol may stimulate uterine contractions.5 While no research has demonstrated that inositol actually has this effect, women who are or could become pregnant should consult a doctor before taking inositol.


1. Levine J, Barak Y, Gonzalves M, et al. Double-blind, controlled trial of inositol treatment of depression. Am J Psychiatry 1995;152:792-4.

2. Levine J, Barak Y, Kofman O, Belmaker RH. Follow-up and relapse analysis of an inositol study of depression. Isr J Psychiatry Relat Sci 1995;32:14-21.

3. Benjamin J, Levine J, Fux M, et al. Double-blind, placebo-controlled, crossover trial of inositol treatment for panic disorder. Am J Psychiatry 1995;152:1084-6.

4. Fux M, Levine J, Aviv A, Belmaker RH. Inositol treatment of obsessive-compulsive disorder. Am J Psychiatry 1996;153:1219-21.

5. Colodny L, Hoffman RL. Inositol—Clinical applications for exogenous use. Altern Med Rev 1998;3:432-47.

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How It Works

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