Supplements
1) Inositol
Inositol, a component of cell membranes, is involved in cell communication and also increases the sensitivity of serotonin receptors [
82].
In a 6-week study of 10 OCD patients, 18 g of inositol improved anxiety and depression symptoms, and caused very few side effects (mostly digestive). In another trial, the same dose only enhanced the effects of SSRIs in 3 out of 10 patients with treatment-resistant OCD [
83,
84].
At this dose, inositol was more effective than fluvoxamine in a clinical trial on 20 people with panic disorder. Because this drug is approved for OCD, further clinical trials comparing both treatments could shed some light on the effectiveness of inositol [
85].
In a brain imaging study of 14 people with OCD, those who responded to inositol showed increased baseline activity in a brain region (left medial prefrontal region) but reduced activity after inositol treatment in other regions (left superior temporal gyrus, middle frontal gyrus and precuneus, and right paramedian post-central gyrus) when compared to non-responders [
86].
2) N-Acetyl Cysteine (NAC)
In a 12-week study of 50 people with compulsive hair pulling (trichotillomania, which is on the OCD spectrum)
NAC improved the symptoms “much or very much” in 56% of the patients (compared with only 16% of the placebo group) [
87].
A systematic review of four pilot trials using NAC for 12-weeks (2,400–3,000 mg/day) concluded that NAC was promising at reducing the severity of OCD symptoms and caused minimal side effects [
88].
However, a more recent 16-week trial on 44 people didn’t find NAC more effective than the placebo [
89]
NAC added to the effects of SSRIs (citalopram) in improving resistance to compulsions in OCD a 10-week clinical trial on 34 children and adolescents [
90].
NAC is thought to work by decreasing glutamate in the synapse and increasing
glutathione. Low glutathione in certain brain regions (cingulate cortex) has been found in patients with OCD [
91,
92].
3) Glycine
Glycine is an amino acid that reduces glutamate function in the cortical region of the brain [
93].
In a 12-week study on 24 OCD patients given 60 grams of glycine as an add-on to conventional therapy, there was a m
inor decrease in OCD symptoms. Importantly,
ten patients dropped out of the study due to the bad taste of glycine, which caused nausea in some cases [
94].
Sarcosine is an inhibitor of glycine uptake, which increases the availability of this amino acid in the brain. In a clinical trial on 25 people with OCD, 8 improved their OCD symptoms after taking sarcosine [
95].
4) Caffeine
In a five-week double-blind trial with 24 patients, 300 mg of caffeine was slightly more effective than 30 mg
dextroamphetamine as an add-on therapy to
improve OCD symptoms. All patients completed the study without adverse events [
96].
The results of this study were recently replicated in a clinical trial on 62 people [
97].
5) Milk Thistle
Milk Thistle is a plant with the flavonoid
silymarin that increased the levels of serotonin in the cortex of mice [
98].
In an 8-week clinical trial on 35 OCD patients, 200 mg milk thistle decreased the symptoms. However, it was less effective than fluoxetine [
99].
6) Borage Oil
Borage is a plant whose flower and oil are both used for OCD.
It had anti-anxiety effects similar to benzodiazepines (ex. Valium) in mice models [
100].
In a 6-week trial on 44 OCD patients, 500 mg of borage extract 1x/day decreased OCD symptoms and anxiety [
101].
However, borage may cause liver toxicity, diarrhea, vomiting, headaches, worsening of asthma and is not safe during pregnancy [
102,
103].
8) Zinc
Scientists have discovered that zinc may play a role in inhibiting excitatory neurotransmission, and activates multiple receptors including GABA [
104,
105].
Zinc was found to be 69.2% lower in mild OCD patients than non-OCD patients in a study on almost 100 people [
106].
In an 8-week study on 23 OCD patients, zinc supplementation (as an add-on to fluoxetine) helped decrease obsessions and compulsions without causing adverse effects [
107].
9) Iron
In a study on almost 100 people,
blood iron levels were 41 – 44% lower in patients with mild and moderate OCD [
106].
Low
iron is also associated with higher tic severity in Tourette syndrome. Iron supplementation decreased the severity of tics over 6-12 months in a clinical trial on 57 children with Tourette. Since there is a relation between this syndrome and OCD, this suggests that iron supplementation may help for OCD as well [
108].
Mind-Body Interventions
1) Exercise
In 5 pilot trials on over 150 people with OCD receiving behavioral or pharmacological therapy, a 12-week aerobic exercise intervention reduced OCD symptoms. The benefits remained for 6 months [
109,
110,
111,
112,
113].
2) Meditation
Mindfulness meditation is thought to help people with anxiety to mentally avoid their triggers. A pilot study with 17 participants showed a reduction in OCD symptoms in patients who partook in mindfulness meditation [
114].
Reducing anxiety may be a beneficial approach to eliminating symptoms of OCD. Read our post on the
Top 31 Natural Treatments for Anxiety for more information.