Sustained-release, extended-release, and other time-release formulations in neuropsychiatry.
Pills and capsules may release their contents within minutes of ingestion; these are immediate-release formulations. Pills and capsules may also release their contents after a time lag, or a little at a time, or in some other predetermined way; these are time-release formulations. Many drugs in psychiatry have been time-release formulated to reduce their local adverse effects in the gastrointestinal tract, to reduce adverse effects associated with peak blood levels, or to artificially extend their half-life. Time-release formulations are associated with the added advantages of convenience of dosing, improved compliance, and less fluctuation in blood levels across the course of the day. A disadvantage of time-release formulations is that they may be incompletely absorbed; this is a serious issue in patients with acute or chronic intestinal hurry disorders, such as gastroenteritis or irritable bowel syndrome. Time-release formulations may also be more expensive than immediate-release formulations.
Department of Psychopharmacology, National Institute of Mental Health and Neurosciences, Bangalore, India candrade@psychiatrist.com.
Chittaranjan
C
Andrade
D003692:Delayed-Action Preparations / Q000009:adverse effects / Q000493:pharmacokinetics; D006801:Humans; D058027:Neuropsychiatry / Q000379:methods*; D011619:Psychotropic Drugs / Q000008:administration & dosage*
D003692:Delayed-Action Preparations; D011619:Psychotropic Drugs