Indications: Pain relief
Mechanism of action: agonist effect at specific, saturable opioid receptors in the CNS and other tissues. Produces a variety of effects including analgesia, constipation, suppression of the cough reflex, respiratory depression from reduced responsiveness of the respiratory centre to CO2, nausea and vomiting via stimulation of the CTZ, changes in mood including euphoria and dysphoria, sedation, mental clouding, and alterations of the endocrine and autonomic nervous systems.
Metabolism & elimination: Hepatic metabolism, renal excretion
Class: Osmotic diuretic
Indications: Promotion of diuresis before irreversible renal failure becomes established, reduction of ICP, treatment of cerebral edema, promotion of urinary excretion of toxic substances.
Mechanism of action: Elevates blood plasma osmolality, resulting in enhanced flow of water from tissues, including the brain and cerebrospinal fluid, into interstitial fluid and plasma. Induces diuresis because it is not reabsorbed in the renal tubule, thereby increasing the osmolality of the glomerular filtrate, facilitating excretion of water, and inhibiting the renal tubular reabsorption of sodium, chloride, and other solutes.
Metabolism & elimination: Metabolized only slightly, if at all, to glycogen in the liver, rapidly excreted renally