The causes of depersonalization can be traced to many things. To make things simpler, we will
        classify these causes into pharmacological (medicine / drug induced) or situational:
        Situational:
      
- Stress - The experience of emotionally stressful situations could give rise to depersonalization episodes, especially to those who have already had them in the past.
- Anxiety - The anxiety surrounding stressful events and other situations could also precipitate, trigger or worsen a depersonalization. Even the anxiety of getting another future depersonalization episode could be enough o trigger this scary cycle.
- Sleep deprivation - Lack of sleep can induce lightheadedness and the other major symptoms associated with depersonalization.
-  Psychological Trauma - Most depersonalization suffers start to have depersonalization
          episodes after a major psychological trauma like childhood abuse, accidents, war and other
          forms of mental and emotional torture.
 by Bastet777
 I am now 46 and I still have depersonalization episodes occasionally. It all started when I was about 10. I have a history of satanic ritual abuse. I began to get the DP symptoms along with nightmares and dream flashbacks. It was very scary. 
- Migraine - Migraine headaches could also be a situational cause of these feelings of detachment. An attack of migraine usually precipitates the depersonalization syndrome in some patients.
-  Epilepsy - This neural disorder could also trigger the depersonalization due to its effects on the
          sensory parts of the nervous system. It can also contribute to the neurotransmitter imbalances
          seen in this dissociative disease.
 
- Interoceptive exposure therapies - The symptoms of depersonalization can also be triggered artificially through a behavioral technique used in the treatment of panic disorder. It consists of a series of exercises designed to bring about the physical sensations of a panic attack. Sometimes, this is also used as a military strategy in enhancing the preparedness of the troops.
-  Caffeine - The caffeine component of coffee and other caffeine containing food and drinks could
          potentially cause a depersonalization episode. Caffeine has a stimulant effect on the body’s
          nervous system and lead to the symptoms associated with this disorder.
 by Blobfish
 I figured out that my DP episodes are made worse by drinking coffee excessively. I needed it during my travels that’s why I take quite a lot of caffeine. The symptoms do not occur immediately with coffee drinking but got worse the more I drink. Even alcohol and those late night drinking binges could potentially lead to your
        depersonalization. Alcohol can bring about the feeling of detachment and other physiologic
        symptoms seen in this disorder.
Pharmacological (Medicine / Drug Induced Depersonalization)
        Benzodiazepine overdose or Benzodiazepine withdrawal syndrome – Benzodiazepine is a drug
        that has a variety of medical and psychological uses. It is used in the treatment of anxiety
        disorders, insomnia, seizure relief and even as an adjunct in alcohol withdrawal protocols. This
        psychoactive medication has been documented to exhibit these depersonalization like side
        effects even in regular doses.
        Cannabis or Marijuana (the “weed”) – The “weed” is popular for its profound psychoactive
        effects that mimic the symptoms of depersonalization. Most often, people who engage in
        marijuana use are doing this for the experience of detachment and the feeling of “high”
        associated with the use of this substance. by monster12348 The Depersonalization all started with my marijuana use. I basically had a marijuana session
        and the next morning I felt weird and all those symptoms followed.
 Shortened Version: Situational Causes: Anxiety
        Stress
        Sleep deprivation
        Psychological Trauma
        Migraine
        Epilepsy
        Interoceptive exposure therapies
        Caffeine
        Alcohol
      
 Pharmacological (Medicine / Drug Induced Depersonalization) Causes:
        Benzodiazepine overdose or Benzodiazepine withdrawal syndrome
        Cannabis or Marijuana (the “weed”)
        Tags:
        Depersonalization causes, depersonalization cause 
What can Worsen the Condition
Forum postings are also rich in resources that tell people first hand information on what makes the DP worse.
by dpdudeRuminating on the condition and the negative state that you have will only make matters worse. You need to try to keep the faith that one day you will see the road to recovery.