主條目:Reuptake inhibitor再回收抑制劑RI
定義[]
- 典型抗憂鬱藥的一種
- The selective serotonin re-uptake inhibitors(SSRIs) are a group of chemically unique antidepressant drugs that specifically inhibit serotonin re-uptake( inhibit SERT), having 300-to 3000-fold greater selectivity as compared to the norepinephrine transporter.
和TCA的比較[]
- Moreover, the SSRls have little blocking activity at muscarinic, α-adrenergic and histaminic H1 receptors.
- Because they have fewer adverse effects and are relatively safe even in overdose, the SSRls have largely replaced tricyclic antidepressants and monoamine oxidase inhibitors as the drugs of choice in treating depression.
機轉[]
- SSRls block the re-uptake of serotonin, leading to increased concentrations of the neurotransmitter in the synaptic clefts.
- Antidepressants, including SSRls, typically take two weeks to produce improvement in mood, and maximum benefit may require twelve weeks or more.
- Patients that do not respond to one antidepressant may respond to another.
治療學[]
- typical depression的首選藥
- bulimia nervosa
- obsessive-compulsive disorder:fluvoxamine
- panic disorder
- premenstrual dysphoric disorder
- generalized anxiety
有的SSRI有抗膽鹼作用[]
例子[]
- SSRls include fluoxetine (Prozac)(百憂解) the prototypic drug, citalopram escitalopram fluvoxamine paroxetine and sertraline .Both citalopram and fluoxetine are recemic mixtrues, of which the respective S-enantiomers are the more potent inhibitors.
- Escitalopram is the pure S-enantiomers of citalopram.
- Only sertraline undergoes significant first-pass metabolism.
副作用[]
- The SSRls can cause gastrointestinal effects, weakness, sexual dysfunction, sleep disturbances, and drug interactions.
對CNS的影響[]
- Paroxetine and fluvoxamine are sedating, and may be useful in patients who have difficulty sleeping.
- Conversely, patients who are fatigued may benefit from one of the more activating antidepressants, fluoxetine.
- Large intakes of SSRls do not cause cardiac arrhythmias, but fluoxetine may cause seizures.
- Antidepressants should be used cautiously in children and teenagers, because about one out of fifty children become more suicidal as a result of SSRl treatment.
sexual dysfunction[]
- SSRl-induced sexual dysfunction can be replaced by the antidepressant with fewer sexual side effects, such as atypical one bupropion or mirtazapine.
serotonin syndrome[]
- All SSRls have the potential to cause a serotonin syndrome characterized by hyperthermia, muscle rigidity, myoclonus (clonic muscle twitching), and changes in mental status and vital signs when used in the presence of a monoamine oxidase inhibitor. Therefore, extended periods of wash-out of each drug class must occur prior to the administration of the other class of drugs.