Thyroid disease in cats is linked to heart disease and a fast heartbeat in conjunction with any other symptoms of thyroid problems is cause for a trip to the vet. Once the hyperthyroidism is treated, your cat's heart rate should return to normal.
Stress reaction â some studies have found that paranoia is more common in people who have experienced severe and ongoing stress â for example, prisoners of war. How stress can trigger paranoia is unclear.
Antidepressants are the other class of medications used in the treatment of paranoid personality disorder. Excessive suspicion may lead to social isolation and depression. And in some cases, depression may cause paranoia. Antidepression medication helps improve the brain chemicals that transmit messages to the neurons.