WBR0093
| 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 75-year-old diabetic woman complains of worsening pain in her feet. The pain started almost 7 months ago and has been increasing in severity lately. The pain is localized in both feet, non-radiating and burning in nature. The patient admits that she has not been compliance with her diabetes medication. Her vitals are blood pressure of 125/80 mmHg, heart rate of 70 beats/minute, temperature of 37 C and respiratory rate of 16 per minute. On physical exam, the patient has decreased sensation in the right and left legs below the knees and decreased Achilles tendon reflexes bilaterally. Laboratory tests reveal an HbA1c level of 15 mg/dL. The patient is educated about the important of adherence to diabetes medication and lifestyle changes to herald the progression of the different complications of diabetes. The physician also considers the prescription of duloxetine to relieve the patient’s symptoms of pain in the feet. Which of the following is the mechanism of action of this drug?]] |
| Answer A | AnswerA::Serotonin reuptake inhibitor |
| 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 bulimia, social phobias, OCD and PTSD. Their side effects are sexual dysfunction, GI distress. In excess they can cause serotonin syndrome if used in combination with drugs that increase Serotonin (confusion, hyperthermia, myoclonus, flushing, diarrhea and cardiovascular collapse).]] |
| Answer B | AnswerB::Serotonin and norepinephrine reuptake inhibitor |
| Answer B Explanation | [[AnswerBExp::Venlaxafine has the same mechanism of action and is used for general anxiety disorder and panic disorders.]] |
| Answer C | AnswerC::Serotonin, norepinephrine and dopamine metabolism inhibitor |
| Answer C Explanation | [[AnswerCExp::MAO (monoamine oxidase) inhibitors increase the levels of NE, 5-HT and DA. They include drugs like: phenelzine, isocarboxacid, selegiline (selective MAO-B inhibitor). They are used mainly for atypical depression. Its major side effects are hypertensive crisis when combined with tyramine, a compound found in cheese and wine.]] |
| 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/panic disorder, and certain pain conditions.]] |
| Right Answer | RightAnswer::B |
| Explanation | [[Explanation::This patient is presenting with peripheral diabetic neuropathy fr which she is prescribed [[[duloxetine]]. Duloxetine is a serotonin–norepinephrine reuptake inhibitor (SNRI). It inhibits norepinephrine and 5-HT reuptake. Its side effects are hypertension, sedation, nausea and stimulant effects.
Wiki-Mnemonics:
Educational Objective: # Duloxetine is an atypical antidepressant, which can be used for peripheral diabetic neuropathy. It inhibits both NE and 5-HT reuptake, having a dual mechanism of action.
References: First Aid 2013 page 472-476]] |
| Approved | Approved::Yes |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |