**12.3 Psychiatric illness and sexuality**

Substance use disorders have varying effects on sexual functions. Alcohol at a smaller quantity may have some stimulatory effect, at higher quantity decreases both desire as well arousal through its effect on testosterone. Cannabis causes detrimental effect on initiation as well as maintenance of erection. Cannabis historically has aphrodisiac effect, but current evidence shows mixed results. Long term use of cannabis has detrimental effect on testosterone. Similarly opioids delay ejaculation in men and improve vaginismus in women, but long term use decreases testosterone as well as lutenising hormone.

The rates of sexual dysfunction in people suffering from schizophrenia, mood disorders, personality disorders, anxiety disorders and eating disorders is very high. In these disorders illness itself can have effect various stages of sexual response cycle, and also medication used can have adverse effects on sexuality. One of the major psychiatric disorder schizophrenia has negative symptoms like blunted affect, anhedonia and avolition itself causes impedance in enjoying sexual life. Loss of libido is one of the symptoms in major depressive disorder. Anxiety disorders are usually associated with premature ejaculation. Mania is associated with increased libido during the episode, at times disinhibited sexual behavior leads to high risk sexual behavior [39].
