Post-traumatic stress disorder
Chronic hallucinatory psychosis
Shared delusional disorder
Sometimes in obsessive–compulsive disorder (OCD)
Dissociative disorders, due to many overlapping symptoms, careful differential diagnosis includes especially dissociative identity disorder. Subtypes
Subtypes of psychosis include:

Postpartum psychosis, occurring shortly after giving birth, primarily associated with maternal bipolar disorder
Monothematic delusions
Myxedematous psychosis
Stimulant psychosis
Tardive psychosis
Shared psychosis (folie à deux)

Cycloid psychosis
Cycloid psychosis is typically an acute, self-limiting form of psychosis with psychotic and mood symptoms that progress from normal to full-blown, usually between a few hours to days, and not related to drug intake or brain injury. While proposed as a distinct entity, clinically separate from schizophrenia and affective disorders, cycloid psychosis is not formally acknowledged by current ICD or DSM criteria. Its unclear place in psychiatric nosology has likely contributed to the limited scientific investigation and literature on the topic. Postpartum psychosis
Postpartum psychosis is a rare yet serious and debilitating form of psychosis. Symptoms range from fluctuating moods and insomnia to mood-incongruent delusions related to the individual or the infant. Women experiencing postpartum psychosis are at increased risk for suicide or infanticide. Many women who experience first-time psychosis from postpartum often have bipolar disorder, meaning they could experience an increase of psychotic episodes even after postpartum. Medical conditions
A very large number of medical conditions can cause psychosis, sometimes called secondary psychosis.
For women, the presence of musculoskeletal disease, heart disease, obstructive sleep apnea, cataplexy, doing physical activities close to bedtime and the presence of a mental disorder were significantly associated with having a higher risk of both PLMD and restless legs syndrome.PLMS seems to have an origin in the spinal cord. In fact, PLMS was suggested to be associated with increased spinal reflexes. Manifestations of PLMS seem to occur mostly in disorders associated with dopaminergic dysfunctions.Hypothesis of low ferritin levels in adult population was raised to explain PLMD where increased RLS severity and increased PLMS were significantly correlated with low ferritin levels. Research evidence suggested iron is possibly contributing to PLMD. Thus, lack of iron may induce inhibition of dopamine formation which might underlie PLMS. Diagnosis
People with PLMD often do not know the cause of their excessive daytime sleepiness and their limb movements are reported by a spouse or sleep partner. PLMD cannot be diagnosed by polysomnogram (PSG) alone, it is necessary to obtain a full medical history and taking into account all available information.Polysomnography is recognized as the assessment method which brings most precise information on sleep quality, sleep structure and physiological parameters during sleep (respiration, heart rate, movements). Therefore, diagnostic of PLMD can usually be established only in laboratory settings.