吉林大学：《药理学》课程PPT教学课件（七年制）Antidepressant drugs

Antidepressant drugs

Antidepressant drugs

Overview Affecting energy,sleep,appetite,libido and the ability to function. Different from schizophrenia Due to a deficiency of monoamines such as norepinephrine and serotonin at certain key sites in the brain

Overview ◼ Affecting energy, sleep, appetite, libido and the ability to function. ◼ Different from schizophrenia ◼ Due to a deficiency of monoamines such as norepinephrine and serotonin at certain key sites in the brain

Tricyclic/polycyclic antidepressants Block norepinephrine,and serotonin uptake into the neuron. Imipramine,amitriptyline,desipramine All have similar therapeutic efficacy,and the choice of drug depends on tolerance of side effects and duration of action

Tricyclic /polycyclic antidepressants ◼ Block norepinephrine, and serotonin uptake into the neuron. ◼ Imipramine, amitriptyline, desipramine ◼ All have similar therapeutic efficacy, and the choice of drug depends on tolerance of side effects and duration of action

Mode of action Inhibition of neurotransmitter uptake: TCA inhibit the neuronal reuptake of norepinephrine,and serotonin into presynaptic nerve terminals. Blocking of receptors:The TCAs also block serotonergic,alpha-adrenergic, histamine,and muscarinic receptors

Mode of action ◼ Inhibition of neurotransmitter uptake: TCA inhibit the neuronal reuptake of norepinephrine, and serotonin into presynaptic nerve terminals. ◼ Blocking of receptors: The TCAs also block serotonergic, alpha-adrenergic, histamine, and muscarinic receptors

actions TCAs elevate mood,improve mental alertness,increase physical activity,and reduce morbid preoccupation in 50 to 70%of individuals with major depression

actions ◼ TCAs elevate mood, improve mental alertness, increase physical activity, and reduce morbid preoccupation in 50 to 70% of individuals with major depression

Therapeutic uses The tricyclic antidepressants are effective in treating severe major depression.Some panic disorders also respond to TCAs.Imipramine has been used to control bed-wetting in children (older than 6 years)by causing contraction of the internal sphincter of the bladder

Therapeutic uses ◼ The tricyclic antidepressants are effective in treating severe major depression. Some panic disorders also respond to TCAs. Imipramine has been used to control bed-wetting in children (older than 6 years) by causing contraction of the internal sphincter of the bladder

Pharmacokinetics Absorption and distribution:The TCAs are well absorbed upon oral administration,are widely distributed and readily penetrate into the CNS.4 to 17 hours for imipramine

Pharmacokinetics ◼ Absorption and distribution: The TCAs are well absorbed upon oral administration, are widely distributed and readily penetrate into the CNS. 4 to 17 hours for imipramine

Adverse effects Antimuscarinic effects: Cardiovascular:Increased catecholamine activity results in cardiac overstimulation ■ Orthostatic hypotension:TCAs block alpha- adrenergic receptors,causing orthostatic hypotension and reflex tachycardia. Sedation

Adverse effects ◼ Antimuscarinic effects: ◼ Cardiovascular: Increased catecholamine activity results in cardiac overstimulation ◼ Orthostatic hypotension: TCAs block alpha￾adrenergic receptors, causing orthostatic hypotension and reflex tachycardia. ◼ Sedation

Precautions The tricyclic antidepressants should be used with caution in manic-depressive patients,since they may unmask manic behavior.The tricyclic antidepressants have a narrow therapeutic index

Precautions ◼ The tricyclic antidepressants should be used with caution in manic-depressive patients, since they may unmask manic behavior. The tricyclic antidepressants have a narrow therapeutic index

SELECTIVE SEROTONIN- REUPTAKE INHIBITORS The selective serotonin-reuptake inhibitors(SSRI)are a new group of chemically unique antidepressant drugs that specifically inhibit serotonin reuptake.This contrasts with the tricyclic antidepressants that nonselectively inhibit the uptake of norepinephrine,and serotonin,and block muscarinic

SELECTIVE SEROTONIN￾REUPTAKE INHIBITORS ◼ The selective serotonin-reuptake inhibitors (SSRI) are a new group of chemically unique antidepressant drugs that specifically inhibit serotonin reuptake. This contrasts with the tricyclic antidepressants that nonselectively inhibit the uptake of norepinephrine, and serotonin, and block muscarinic