Pain can do it too. If you have a painful condition e.g. arthritis, you are more likely to have bad dreams and nightmares because the pain interferes with the normal phases of sleep. A large study of the (ahem) elderly showed that bad dreams were much more likely to be reported in arthritis and post-surgery. Drugs, as has been said, especially opioids, can be especially potent, but the study disambiguated the effect of the drugs from the pain. However, one normally forgets the content of dreams/'mares, so if you are persistently ruminating on their content and it is upsetting, it would be good to get some advice or even CBT.
Air Conditioning units ,any advice please?
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