Children who experienced the death of a family member or a close friend or know someone with a chronic illness have more frequent nightmares than those who are only faced with stress from school or stress from social aspects of daily life. A study researching the causes of nightmares focuses on patients who have sleep apnea. The study was conducted to determine whether or not nightmares may be caused by sleep apnea, or being unable to breathe. In the nineteenth century, authors believed that nightmares were caused by not having enough oxygen, therefore it was believed that those with sleep apnea had more frequent nightmares than those without it. The results actually showed that healthy people have more nightmares than sleep apnea patients. Another study supports the hypothesis. In this study, 48 patients (aged 20–85 yrs) with obstructive airways disease (OAD), including 21 with and 27 without asthma, were compared with 149 sex- and age-matched controls without respiratory disease. OAD subjects with asthma reported approximately 3 times as many nightmares as controls or OAD subjects without asthma. The evolutionary purpose of nightmares then could be a mechanism to awaken a person who is in danger. Lucid-dreaming advocate Stephen LaBerge has outlined a possible reason for how dreams are formulated and why nightmares occur. To LaBerge, a dream starts with an individual thought or scene, such as walking down a dimly lit street.
: 291  Ketorolac is used to treat idiopathic pericarditis, where it reduces inflammation.For systemic use, ketorolac can be administered orally, under the tongue, by intramuscular injection, intravenously, and by nasal spray. Usually, it is initially administered by intramuscular injection or intravenously, with oral therapy used as a continuation after the initial IM or IV dose.Ketorolac is also used as an eye drop. It can be given during eye surgery to help with pain, and is effective in treating ocular itching. The eye drops are associated with decreased development of macular edema after cataract surgery. Ketorolac eye drops have also been used to manage pain from corneal abrasions.During treatment with ketorolac, clinicians monitor for the manifestation of adverse effects. Lab tests, such as liver function tests, bleeding time, BUN, serum creatinine and electrolyte levels are often used and help to identify potential complications. Contraindications
Ketorolac is contraindicated in those with hypersensitivity, allergies to the medication, cross-sensitivity to other NSAIDs, prior to surgery, history of peptic ulcer disease, gastrointestinal bleeding, alcohol intolerance, renal impairment, cerebrovascular bleeding, nasal polyps, angioedema, and asthma. Recommendations exist for cautious use of ketorolac in those who have experienced cardiovascular disease, myocardial infarction, stroke, heart failure, coagulation disorders, renal impairment, and hepatic impairment. Adverse effects
A common (>10%) side effect is drowsiness. Infrequent (<1%) side effects include paresthesia, prolonged bleeding time, injection site pain, purpura, sweating, abnormal thinking, increased production of tears, edema, pallor, dry mouth, abnormal taste, urinary frequency, increased liver enzymes, itching and others. Platelet function can be decreased by use of ketorolac.