WBR0094
| Author | PageAuthor::Gonzalo Romero |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Behavioral Science/Psychiatry, MainCategory::Pharmacology |
| Sub Category | SubCategory::Neurology |
| Prompt | [[Prompt::A 25-year-old male complains of generalized fatigue for over more than 7 months. Upon interrogation, the patient reports he has generally unhappy and lacks motivation at work. He spends most his time at home sleeping and when he wakes up he is either watching TV or eating fast food. The patient also mentions that he feels heaviness in his arms and legs and has no energy to move or go out of the house. He denies suicidal ideations or feeling of worthlessness. The patient is started on a medication to relieve his symptoms. Which of the following is the mechanism of action of the drug most likely prescribed to this patient?]] |
| Answer A | AnswerA::Inhibits serotonin reuptake |
| Answer A Explanation | [[AnswerAExp::SSRIs specifically inhibit 5-HT reuptake. Examples are paroxetine, sertraline, citalopram and sertraline. They are used for depression, general anxiety disorder, bulimia, social phobias, OCD and PTSD]] |
| Answer B | AnswerB::Inhibits serotonin and NE reuptake |
| Answer B Explanation | [[AnswerBExp::Duloxetine and venlafaxine are DOBLE HITTERS= inhibit both NE and serotonin reuptake. They are atypical antidepressants, which can be used for neuropathic pain.]] |
| Answer C | AnswerC::Inhibits serotonin, NE and Dopamine metabolism |
| Answer C Explanation | AnswerCExp:: |
| Answer D | AnswerD::Alpha-2 receptor antagonist |
| Answer D Explanation | [[AnswerDExp::Mirtazapine is an alpha-2 receptor antagonist. It is an atypical antidepressant which causes appetite increase and weight gain, therefore useful in the elderly and anorexic patients.]] |
| Answer E | AnswerE::Alpha-2 receptor agonist |
| Answer E Explanation | [[AnswerEExp::Methyldopa and clonidine are selective for α2-adrenergic agonists. Methyldopa is used to treat hypertension, especially in pregnant women. Clonidine can be used for hypertension, anxiety or panic disorder, and certain pain conditions.]] |
| Right Answer | RightAnswer::C |
| Explanation | [[Explanation::This patient is presenting with atypical depression, the most common subtype of depression. Atypical depression is characterized by hypersomnia and increase in appetite which leads to weight gain. It is also associated with paralysis or a heavy feeling in arms and legs and long-term interpersonal rejection sensitivity. Atypical depression is also characterized by mood reactivity; the patient is able to improve his mood to positive events. The treatment of choice is a MAO inhibitor, which inhibits 5-HT, norepinephrine and dopamine metabolism. MOIs include phenelzine, tranylcypromine, isocarboxacid and selegiline which is a selective MAO-B inhibitor. MOIs are used mainly for atypical depression. The major side effects of MOI are hypertensive crisis when combined with tyramine, a compound found in cheese and wine.
WikiDoc Mnemonics: Duloxetine and venlafaxine are DOBLE HITTERS= They inhibit both norepinephrine and serotonin reuptake. |
| Approved | Approved::Yes |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |