There have been no randomized trials examining the effect of hydrocortisone given after the first week of life or used to treat infants with prolonged ventilator dependence. One retrospective cohort study compared infants who required assisted ventilation and oxygen after the first one to two weeks of age and received hydrocortisone with a group of healthier infants who did not receive hydrocortisone.  Infants treated with hydrocortisone experienced decreasing oxygen requirements and were successfully weaned from assisted ventilation. After seven days of treatment, there were no differences in oxygen requirements between the two groups. On follow-up, there were no differences in head circumference, neurological outcome, psychomotor development or school performance. Magnetic resonance imaging performed at eight years of age on a similar cohort of infants treated with hydrocortisone showed that although, overall, children born preterm had significantly reduced grey matter volumes compared to term children, there were no differences in the intracranial volumes, grey matter volumes or white matter volumes between children who did and did not receive hydrocortisone for treatment of CLD.  There were also no differences in neurocognitive outcomes, assessed using the Wechsler Intelligence Scales for Children.
The most commonly reported side effects were: oral thrush , nausea , headache , and pain in the pharynx or larynx . More rarely reported side effects (occurring in <1% of patients during the clinical trial) include: tachycardia , palpitations , dry mouth , allergic reaction ( bronchospasm , dermatitis , hives ), pharyngitis , muscle spasms , tremor , dizziness , insomnia , nervousness , and hypertension . Patients experiencing an allergic reaction or increase in difficulty breathing while using this medication should immediately discontinue its use and contact their physician. 
Oral and injectable systemic corticosterois are steroid hormones prescribed to decrease inflammation in diseases and conditions such as arthritis (rheumatoid arthritis, for example), ulcerative colitis, Crohn's disease, asthma, bronchitis, some skin rashes, and allergic or inflammatory conditions that involve the nose and eyes. Examples of systemic corticosteroids include hydrocortisone (Cortef), cortisone, prednisone (Prednisone Intensol), prednisolone (Orapred, Prelone), and methylprednisolone (Medrol, Depo-Medrol, Solu-Medrol). Some of the side effects of systemic corticosteroids are swelling of the legs, hypertension, headache, easy bruising, facial hair growth, diabetes, cataracts, and puffiness of the face.