Category: Drugs acting in the central nervous system

Opioid is any substance that can produce morphine like effects. Opium is an extract of the juiceof the poppy Papaver somniferum. Opium contains many alkaloids related to morphine. Themain group of drugs that are discussed in section are divided into two; morphine analogues andsynthetic derivatives.Morphine analogues. Compounds closely related in structure to morphine. They may…

Depression is one of the most common psychic disorders. Antidepressants are the drugs whichare mainly used in the management of depression.Types of antidepressant drugs Atypical antidepressantsPharmacokineticsMost tricyclics are incompletely absorbed and undergo significant first-pass metabolism. Highlyprotein bound and relatively high lipid solubility. Fluoxetine (Selective Serotonin ReuptakeInhibitors (SSRIs)) is well absorbed. The MAO inhibitors are readily…

Seizure is associated with the episodic high frequency discharge of impulses by a group ofneurons in the brain.Seizure may be partial or generalized depending on the location and the spread of theabnormal neuronal discharge. The attack mainly involves motor, sensory or behavioralphenomena.Partial seizures are often associated with damage to the brain, whereas generalized seizureoccurs without…

BenzodiazepinesBenzodiazepines are well absorbed when given orally. They bind strongly to plasma proteins,however, many of them accumulate gradually in the body fat (i.e. they are highly lipid soluble).Benzodiazepines are inactivated by the liver and excreted in the urine.Based on their duration of action roughly divided into short acting (flurazepam, triazolam),medium acting (alprazepam, lorazepam) and long…

Anxiolytic drugs are used to treat the symptoms of anxiety, where as hypnotic drugs used totreat insomnia. The same drugs are used for both purposes.Classes of anxiolytic and hypnotic drugs: The main groups of the drugs are:

General anesthesia involves the physiological changes: Reversible loss of response to painfulstimuli, loss of consciousness and loss of motor and autonomic reflexes. Loss of consciousnessis associated with inhibition of the activity of reticular formation.General anesthetics are administered by inhalation or by intravenous routes. They are classifiedinto two on the basis of their route of administration…

To facilitate the understanding of the pharmacological and unwanted effects of CNS drugs, thephysiological functions of the main CNS neurotransmitters are discussed briefly.Noradrenaline. Noradrenergic transmission is important in control of mood (functional deficiencyresulting depression) controlling wakefulness, and alertness.Dopamine. Dopamine is important in motor control (Parkinsonism is due to dopaminedeficiency), has behavioural effects (excessive dopamine activity…