I will mention the following substance that has helped me in dealing with OCD, and although some might find it unlikely, there is some limited support in the scientific literature for the use of this substance in treating OCD:
Dexedrine (D-amphetamine)
As odd as it may seem, when I take Dexedrine or Adderall, it seems to minimize many of the intrusive thoughts in my head, and help me to focus on whatever I am trying to do, without the distraction of my usual OCD rituals. Obviously, the use of amphetamine can raise anxiety in people. And it's impossible to use at night time, or I will never get to sleep. But the use of Dexedrine and other amphetamines during the day does seem to help me shut out the intrusive thoughts and behaviors, and help me focus on whatever I am doing.
It is certainly not the favored treatment for OCD, which are of course the SSRI's. But Dexedrine does seem to help me and some others, and it doesn't have the same libido problems as the SSRI's. If anything, it enhances my libido, although it does make it more difficult to get an erection while using it.
Your mileage may vary, as it does for any other substance. Use at your own risk, or don't.
“D-Amphetamine 30 mg, studied in a single-dose, double-blind, placebo-controlled trial, was associated with a significant decrease in self-rated symptoms about 6 hours after the dose, independently of effects on mood (184). D-Amphetamine had an acute anti-OCD effect in 11 of 12 subjects (92%). With placebo, neither the self-ratings nor the blinded observer’s ratings decreased significantly. Two patients continued D-amphetamine at a dose of 10–20 mg/day for “several weeks” with continued response. In a small (n=11), double-blind, placebo-controlled, crossover study of single doses of methylphenidate 40 mg and D-amphetamine 30 mg, both taken orally, the latter drug was associated with a significantly greater reduction in OCD symptom rating than was placebo (185). Five of the 11 subjects (45%) had a ≥50% decrease in their OCD scores after D-amphetamine, two (18%) after methylphenidate, and only one (9%) after placebo. In both studies, the decrease in OCD symptoms was independent of mood effects. Open-label methylphenidate, 40 mg once orally, produced no significant effect on OCD or mood 4 hours later in a small study (n=13), although four patients had a 50% decrease in an OCD rating scale score (489). Case reports exist of OCD benefit after treating co-occurring attention-deficit disorder with stimulants. The presence of tics or Tourette’s disorder does not contraindicate the use of stimulants to treat ADHD co-occurring with OCD, although methylphenidate appears to be better tolerated in this situation than D-amphetamine (490).”
184. Insel TR, Hamilton JA, Guttmacher LB, Murphy DL: D-Amphetamine in obsessive-compulsive disorder. Psychopharmacology (Berl) 1983; 80:231–235 [A]
185. Joffe RT, Swinson RP, Levitt AJ: Acute psychostimulant challenge in primary obsessive-compulsive disorder. J Clin Psychopharmacol 1991; 11:237–241 [A]
489. Joffe RT, Swinson RP: Methylphenidate in primary obsessive-compulsive disorder. J Clin Psychopharmacol 1987; 7:420–422
490. Kurlan R: Tourette’s syndrome: are stimulants safe? Curr Neurol Neurosci Rep 2003; 3:285–288 [G]
https://psychiatryonline.org/pb/assets/raw/sitewide/practice_guidelines/guidelines/ocd.pdf