CNS drugs (antiepileptics, anesthetics)

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 1: A 24-year-old man presents to his primary care physician for a persistent and low grade headache as well as trouble focusing. The patient was seen in the emergency department 3 days ago after hitting his head on a branch while biking under the influence of alcohol. His head CT at the time was normal, and the patient was sent home with follow up instructions. Since the event, he has experienced trouble focusing on his school work and feels confused at times while listening to lectures. He states that he can’t remember the lectures and also says he has experienced a sensation of vertigo at times. On review of systems, he states that he has felt depressed lately and has had trouble sleeping, though he denies any suicidal or homicidal ideation. His temperature is 98.2°F (36.8°C), blood pressure is 122/65 mmHg, pulse is 70/min, respirations are 12/min, and oxygen saturation is 98% on room air. The patient’s neurological and cardiopulmonary exam are within normal limits. Which of the following is the best next step in management?

• A. Thiamine
• B. Cognitive behavioral therapy
• C. Rest and primary care follow up (Correct Answer)
• D. CT scan of the head without contrast
• E. Fluoxetine

CNS drugs (antiepileptics, anesthetics) Explanation: ***Rest and primary care follow up*** - The patient's symptoms of **headache**, **confusion**, **vertigo**, **difficulty concentrating**, and **sleep disturbances** following a minor head injury are highly suggestive of a **concussion** or **post-concussive syndrome**. - For concussion, the primary management involves **physical and cognitive rest** to allow the brain to heal, along with close follow-up to monitor symptom resolution or worsening. *Thiamine* - **Thiamine** (vitamin B1) is primarily indicated for conditions such as **Wernicke encephalopathy** or **Korsakoff syndrome**, often associated with chronic alcohol abuse and malnutrition. - While the patient had a history of alcohol use, his acute symptoms are more consistent with head trauma, and there's no indication of a **thiamine deficiency**-related neurological syndrome. *Cognitive behavioral therapy* - **Cognitive Behavioral Therapy (CBT)** is a psychotherapeutic intervention used for conditions like **depression**, **anxiety disorders**, and **insomnia**. - While the patient reports feeling depressed and having trouble sleeping, these symptoms can be part of post-concussive syndrome, and initial management should prioritize brain rest before focusing solely on CBT for mood and sleep. *CT scan of the head without contrast* - A **CT scan of the head without contrast** was already performed 3 days ago and was normal, effectively ruling out acute intracranial hemorrhage or major structural damage immediately after the injury. - Given the normal initial CT and the constellation of symptoms consistent with **concussion**, a repeat CT scan is unlikely to provide additional useful information and is not the best immediate next step. *Fluoxetine* - **Fluoxetine** is a Selective Serotonin Reuptake Inhibitor (SSRI) used to treat **depression** and **anxiety disorders**. - While the patient reports feeling depressed, initiating an antidepressant is not the immediate best step for a suspected concussion; depression and sleep issues can be sequelae of a concussion, and management should initially focus on concussion recovery.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 2: A 10-year-old girl is brought to the emergency department by her mother 30 minutes after having had a seizure. When her mother woke her up that morning, the girl's entire body stiffened and she started shaking vigorously for several minutes. Her mother also reports that over the past few months, her daughter has had multiple episodes of being unresponsive for less than a minute, during which her eyelids were fluttering. The girl did not recall these episodes afterwards. Upon arrival, she appears drowsy. Neurologic examination shows no abnormalities. Which of the following is the most appropriate pharmacotherapy to prevent recurrence of this patient's symptoms?

• A. Valproate (Correct Answer)
• B. Topiramate
• C. Lorazepam
• D. Ethosuximide
• E. Phenytoin

CNS drugs (antiepileptics, anesthetics) Explanation: ***Valproate*** - The patient's presentation with **tonic-clonic seizures** and brief unresponsiveness with **eyelid fluttering** (absence seizures) indicates a generalized epilepsy syndrome, likely **juvenile myoclonic epilepsy**. - **Valproate** is a broad-spectrum antiepileptic drug effective against both generalized tonic-clonic and absence seizures, making it the most appropriate choice for this combination. *Topiramate* - While **topiramate** is a broad-spectrum antiepileptic, it is not considered first-line for combined absence and generalized tonic-clonic seizures due to its side effect profile, which includes **cognitive impairment** and **kidney stones**. - It can also **exacerbate absence seizures** in some patients. *Lorazepam* - **Lorazepam** is a benzodiazepine primarily used for the acute management of **status epilepticus** and acute seizure termination due to its rapid onset of action. - It is not suitable for long-term seizure prevention or maintenance therapy due to its sedative effects and potential for **tolerance and dependence**. *Ethosuximide* - **Ethosuximide** is highly effective specifically for **absence seizures** and is considered first-line for childhood absence epilepsy. - However, it has little to no efficacy against **generalized tonic-clonic seizures**, which this patient also experiences, making it an insufficient monotherapy. *Phenytoin* - **Phenytoin** is effective for **focal (partial) seizures** and **generalized tonic-clonic seizures** but is generally less effective for certain generalized epilepsies, such as juvenile myoclonic epilepsy. - It is not effective for **absence seizures** and can sometimes worsen them.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 3: A 5-year-old boy presents to his pediatrician along with his parents due to episodes of “staring into space.” This symptom occurs several times a day and lasts only a few seconds. During these episodes, the boy does not respond to verbal or physical stimulation, and his parents deny him falling down or shaking. After the episode, the boy returns to his normal activity and is not confused. The parents deny any history of head trauma, recent medication use, or infection. Neurological exam is unremarkable. His episode is precipitated as he blows at a pinwheel. An EEG is performed, which shows 3-Hz spike and waveform. Which of the following is the best treatment option for this patient?

• A. Zonisamide
• B. Valproic acid
• C. Ethosuximide (Correct Answer)
• D. Lamotrigine
• E. Levetiracetam

CNS drugs (antiepileptics, anesthetics) Explanation: ***Ethosuximide*** - This patient presents with **childhood absence epilepsy (CAE)**, characterized by brief episodes of "staring into space," unresponsiveness, post-ictal normality, and precipitated by **hyperventilation** (like blowing a pinwheel). The EEG finding of **3-Hz spike-and-wave discharges** is pathognomonic for CAE. - **Ethosuximide** is the first-line and most effective treatment for typical absence seizures, operating by blocking **T-type calcium channels** in thalamic neurons. *Zonisamide* - Zonisamide is a broad-spectrum antiepileptic drug that can be used for various seizure types, including **focal and generalized convulsive seizures**, but it is not the first-line treatment for typical absence seizures. - Its mechanism involves blocking **sodium and calcium channels**, and its efficacy in absence seizures is not as well-established as ethosuximide. *Valproic acid* - Valproic acid is effective for both **absence seizures and generalized tonic-clonic seizures**, particularly when both types occur. - However, due to its potential for more significant side effects, including **hepatotoxicity** and **teratogenicity**, it is generally considered a second-line treatment for uncomplicated CAE, especially in young children. *Lamotrigine* - Lamotrigine is an antiepileptic drug used for various seizure types, including **focal, generalized tonic-clonic**, and some **absence seizures**, but it is not considered first-line for typical absence seizures. - It primarily acts by blocking **voltage-gated sodium channels** and can be used as an add-on therapy or for refractory cases. *Levetiracetam* - Levetiracetam is a broad-spectrum antiepileptic effective for **focal, myoclonic, and generalized tonic-clonic seizures**. - While it can be used for absence seizures, it is generally **less effective** than ethosuximide or valproic acid for typical absence seizure control.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 4: A 37-year-old man is presented to the emergency department by paramedics after being involved in a serious 3-car collision on an interstate highway while he was driving his motorcycle. On physical examination, he is responsive only to painful stimuli and his pupils are not reactive to light. His upper extremities are involuntarily flexed with hands clenched into fists. The vital signs include temperature 36.1°C (97.0°F), blood pressure 80/60 mm Hg, and pulse 102/min. A non-contrast computed tomography (CT) scan of the head shows a massive intracerebral hemorrhage with a midline shift. Arterial blood gas (ABG) analysis shows partial pressure of carbon dioxide in arterial blood (PaCO2) of 68 mm Hg, and the patient is put on mechanical ventilation. His condition continues to decline while in the emergency department and it is suspected that this patient is brain dead. Which of the following results can be used to confirm brain death and legally remove this patient from the ventilator?

• A. Electrocardiogram
• B. Apnea test (Correct Answer)
• C. Lumbar puncture and CSF culture
• D. Electromyography with nerve conduction studies
• E. CT scan

CNS drugs (antiepileptics, anesthetics) Explanation: ***Correct: Apnea test*** - The **apnea test** is a **mandatory component** of brain death determination according to American Academy of Neurology (AAN) guidelines - It directly confirms the **irreversible absence of brainstem function** by demonstrating no respiratory drive despite adequate stimulus (PaCO2 ≥60 mm Hg or 20 mm Hg rise from baseline) - This patient already has a PaCO2 of 68 mm Hg, making the apnea test particularly relevant for confirmation - Brain death requires both **clinical examination** (absent brainstem reflexes, coma) and a **positive apnea test** to legally declare death and discontinue mechanical ventilation - The apnea test is performed by disconnecting the ventilator, providing supplemental oxygen, and observing for any respiratory effort while PaCO2 rises to adequate levels *Incorrect: CT scan* - While a **CT scan showing massive intracerebral hemorrhage with midline shift** provides anatomical evidence of severe, irreversible structural brain damage, it is **NOT sufficient to confirm brain death** - CT imaging is used to establish the **etiology** and rule out reversible causes, but does not directly test brainstem function - Brain death is a **clinical and functional diagnosis**, not purely an anatomical one—imaging alone cannot confirm cessation of all brain function - A patient can have devastating structural damage on CT but still retain some brainstem reflexes *Incorrect: Electrocardiogram* - An **electrocardiogram (ECG)** measures cardiac electrical activity and provides no information about brain or brainstem function - Cardiac activity commonly persists after brain death due to the heart's intrinsic automaticity - ECG findings are irrelevant to brain death determination *Incorrect: Lumbar puncture and CSF culture* - **Lumbar puncture and CSF culture** are used to diagnose CNS infections (meningitis, encephalitis) or inflammatory conditions - These tests are **completely irrelevant** for brain death diagnosis, which is based on irreversible cessation of all brain function, not infection - In this trauma case with known intracerebral hemorrhage, LP would be contraindicated due to increased intracranial pressure and risk of herniation *Incorrect: Electromyography with nerve conduction studies* - **EMG and nerve conduction studies** assess peripheral nerve and muscle function, used for diagnosing neuromuscular disorders - These tests provide no information about brain or brainstem function - They are not part of brain death determination protocols

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 5: A 16-year-old girl who recently immigrated to the United States from Bolivia presents to her primary care physician with a chief complaint of inattentiveness in school. The patient's teacher describes her as occasionally "day-dreaming" for periods of time during which the patient does not respond or participate in school activities. Nothing has helped the patient change her behavior, including parent-teacher conferences or punishment. The patient has no other complaints herself. The only other concern that the patient's mother has is that upon awakening she notices that sometimes the patient's arm will jerk back and forth. The patient states she is not doing this intentionally. The patient has an unknown past medical history and is currently not on any medications. On physical exam you note a young, healthy girl whose neurological exam is within normal limits. Which of the following is the best initial treatment?

• A. Ethosuximide
• B. Valproic acid (Correct Answer)
• C. Carbamazepine
• D. Cognitive behavioral therapy
• E. Lamotrigine

CNS drugs (antiepileptics, anesthetics) Explanation: ***Valproic acid*** - This patient presents with symptoms highly suggestive of **juvenile myoclonic epilepsy (JME)**, characterized by **absence seizures** ("day-dreaming") and **myoclonic jerks**, particularly upon awakening. Valproic acid is considered a first-line agent for JME due to its broad spectrum of action against various seizure types. - While ethosuximide is effective for absence seizures, valproic acid is preferred in JME because it also effectively controls the associated myoclonic jerks, addressing both seizure types seen in this patient. *Ethosuximide* - Ethosuximide is the drug of choice for **absence seizures** only, effectively preventing the "day-dreaming" spells. - However, it is not effective against the **myoclonic jerks** described by the patient's mother, which are a characteristic feature of juvenile myoclonic epilepsy. *Carbamazepine* - Carbamazepine is primarily used for **focal (partial) seizures** and **tonic-clonic seizures**. - It can actually **exacerbate absence and myoclonic seizures**, making it an inappropriate choice for this patient's presentation. *Cognitive behavioral therapy* - Cognitive behavioral therapy (CBT) is a **psychological intervention** primarily used for mental health conditions like anxiety, depression, or behavioral disorders. - While helpful for addressing emotional or behavioral responses to a chronic illness, it does not treat the underlying **electrical abnormalities in the brain** that cause seizures. *Lamotrigine* - Lamotrigine is a broad-spectrum antiepileptic drug that can be effective for various seizure types, including **absence and myoclonic seizures**. - However, it can sometimes **exacerbate myoclonic seizures** in some individuals with JME, and while sometimes used as an alternative, valproic acid is generally the first-line choice for its established efficacy in controlling all seizure types in JME.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 6: A 25-year-old man is brought to the emergency department by paramedics with a seizure lasting over 30 minutes. The patient's neighbors found him outside his apartment with all four limbs flailing and not responding to his name. No significant past medical history. On physical examination, the patient continues to be unresponsive and slightly cyanotic with irregular breathing. His teeth are clenched tightly. Intravenous glucose and an anticonvulsant medication are administered. Which of the following is the mechanism of action of the drug that was most likely administered to stop this patient’s seizure?

• A. Blockage of voltage-gated calcium channels
• B. Blockage of T-type calcium
• C. Increase in frequency of chloride channel opening (Correct Answer)
• D. Prolongation of chloride channel opening
• E. Inactivation of sodium channels

CNS drugs (antiepileptics, anesthetics) Explanation: ***Increase in frequency of chloride channel opening*** - The patient is experiencing **status epilepticus** (seizure lasting >5 minutes or recurrent seizures without full recovery of consciousness), which requires rapid intervention, typically with a **benzodiazepine**. - **Benzodiazepines** (e.g., lorazepam, diazepam) act by binding to the **GABA-A receptor** and increasing the **frequency of chloride channel opening**, leading to neuronal hyperpolarization and reduced excitability. *Blockage of voltage-gated calcium channels* - This mechanism is characteristic of **gabapentin** and **pregabalin**, which are used for **neuropathic pain** and adjunctive seizure therapy, but not typically as first-line for status epilepticus. - Blocking voltage-gated calcium channels primarily reduces **neurotransmitter release**, which is a slower mechanism of action compared to GABAergic potentiation for acute seizure cessation. *Blockage of T-type calcium* - This is the primary mechanism of action for **ethosuximide**, which is used specifically for **absence seizures**. - Absence seizures are brief, generalized non-convulsive seizures, distinct from the generalized tonic-clonic seizure described in the patient. *Prolongation of chloride channel opening* - This mechanism is associated with **barbiturates** (e.g., phenobarbital), which also act on the GABA-A receptor but cause a **prolonged opening** of the chloride channel at high concentrations. - While barbiturates can be used for refractory status epilepticus, **benzodiazepines** are generally preferred as first-line due to a better safety profile and fewer side effects compared to barbiturates. *Inactivation of sodium channels* - This mechanism is characteristic of several anticonvulsant drugs, including **phenytoin, carbamazepine, and lamotrigine**. - These drugs are typically used for **long-term seizure control** and prevention, not as first-line agents for aborting an ongoing status epilepticus, due to their slower onset of action.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 7: An epidemiologist is evaluating the efficacy of Noxbinle in preventing HCC deaths at the population level. A clinical trial shows that over 5 years, the mortality rate from HCC was 25% in the control group and 15% in patients treated with Noxbinle 100 mg daily. Based on this data, how many patients need to be treated with Noxbinle 100 mg to prevent, on average, one death from HCC?

• A. 20
• B. 73
• C. 10 (Correct Answer)
• D. 50
• E. 100

CNS drugs (antiepileptics, anesthetics) Explanation: ***10*** - The **number needed to treat (NNT)** is calculated by first finding the **absolute risk reduction (ARR)**. - **ARR** = Risk in control group - Risk in treatment group = 25% - 15% = **10%** (or 0.10). - **NNT = 1 / ARR** = 1 / 0.10 = **10 patients**. - This means that **10 patients must be treated with Noxbinle to prevent one death from HCC** over 5 years. *20* - This would result from an ARR of 5% (1/0.05 = 20), which is not supported by the data. - May arise from miscalculating the risk difference or incorrectly halving the actual ARR. *73* - This value does not correspond to any standard calculation of NNT from the given mortality rates. - May result from confusion with other epidemiological measures or calculation error. *50* - This would correspond to an ARR of 2% (1/0.02 = 50), which significantly underestimates the actual risk reduction. - Could result from incorrectly calculating the difference as a proportion rather than absolute percentage points. *100* - This would correspond to an ARR of 1% (1/0.01 = 100), grossly underestimating the treatment benefit. - May result from confusing ARR with relative risk reduction or other calculation errors.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 8: A 57-year-old man was brought into the emergency department unconscious 2 days ago. His friends who were with him at that time say he collapsed on the street. Upon arrival to the ED, he had a generalized tonic seizure. At that time, he was intubated and is being treated with diazepam and phenytoin. A noncontrast head CT revealed hemorrhages within the pons and cerebellum with a mass effect and tonsillar herniation. Today, his blood pressure is 110/65 mm Hg, heart rate is 65/min, respiratory rate is 12/min (intubated, ventilator settings: tidal volume (TV) 600 ml, positive end-expiratory pressure (PEEP) 5 cm H2O, and FiO2 40%), and temperature is 37.0°C (98.6°F). On physical examination, the patient is in a comatose state. Pupils are 4 mm bilaterally and unresponsive to light. Cornea reflexes are absent. Gag reflex and cough reflex are also absent. Which of the following is the next best step in the management of this patient?

• A. Second opinion from a neurologist
• B. Withdraw ventilation support and mark time of death
• C. Electroencephalogram
• D. Repeat examination in several hours
• E. Apnea test (Correct Answer)

CNS drugs (antiepileptics, anesthetics) Explanation: ***Apnea test*** - The patient exhibits classic signs of **brain death**, including a **coma**, fixed and dilated pupils, and absent brainstem reflexes (corneal, gag, cough). The next step is to perform an apnea test to confirm the absence of spontaneous respiratory drive. - An apnea test confirms brain death by demonstrating the **absence of respiratory effort** despite a rising pCO2, provided that spinal cord reflexes are not mistaken for respiratory efforts. *Second opinion from a neurologist* - While consulting a neurologist is often helpful in complex neurological cases, the current clinical picture presents such clear signs of brain death that **further confirmatory testing** for brain death (like the apnea test) is more immediately indicated before seeking additional opinions on diagnosis. - A second opinion would typically be sought to confirm the diagnosis or guide management, but establishing brain death requires a specific protocol which is incomplete without the apnea test. *Withdraw ventilation support and mark time of death* - It is **premature to withdraw ventilation** before brain death is unequivocally confirmed by all necessary clinical and confirmatory tests, including the apnea test. - Withdrawing support without full confirmation could lead to ethical and legal issues, as the patient might still have residual brainstem function, however minimal. *Electroencephalogram* - An **EEG** can show absent electrical activity, supporting brain death, but it is **not a mandatory part of the core brain death criteria** in many protocols, especially when clinical signs are clear and an apnea test can be performed. - The primary diagnostic criteria for brain death usually prioritize clinical examination and the apnea test for proving irreversible cessation of all brain functions. *Repeat examination in several hours* - Repeating the examination in several hours is typically done if there are **confounding factors** (e.g., severe hypothermia, drug intoxication) that might mimic brain death, or if the initial assessment is incomplete. - In this case, there are no mentioned confounding factors, and the immediate priority is to complete the brain death protocol with an apnea test, given the current clear clinical picture.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 9: A group of researchers is studying various inhaled substances to determine their anesthetic properties. In particular, they are trying to identify an anesthetic with fast onset and quick recovery for use in emergencies. They determine the following data: Inhalational anesthetic Blood-gas partition coefficient A 0.15 B 0.92 C 5.42 Which of the following statements is accurate with regard to these inhaled anesthetic substances?

• A. Agent C has the fastest onset of action
• B. Agent A has the fastest onset of action (Correct Answer)
• C. Agent B is the most potent
• D. Agent B has the fastest onset of action
• E. Agent A is the most potent

CNS drugs (antiepileptics, anesthetics) Explanation: ***Agent A has the fastest onset of action*** - **Agent A** has the lowest blood-gas partition coefficient (0.15), indicating very low solubility in blood. - A **low blood-gas partition coefficient** means the anesthetic quickly equilibrates between the lungs and blood, leading to a rapid rise in partial pressure in the brain and thus **fast onset of action** and **quick recovery**. *Agent C has the fastest onset of action* - **Agent C** has the highest blood-gas partition coefficient (5.42), indicating high solubility in blood. - High solubility means the anesthetic takes longer to saturate the blood and reach the brain, resulting in a **slow onset of action** and **slow recovery**. *Agent B is the most potent* - **Potency** of an inhaled anesthetic is inversely related to its **Minimum Alveolar Concentration (MAC)**, not directly to its blood-gas partition coefficient. - While a higher blood-gas coefficient can sometimes correlate with other properties, it does not directly determine potency. *Agent B has the fastest onset of action* - **Agent B** has a blood-gas partition coefficient of 0.92, which is higher than Agent A (0.15). - A higher blood-gas partition coefficient means the anesthetic is more soluble in blood, leading to a **slower onset of action** compared to Agent A. *Agent A is the most potent* - **Agent A** has the lowest blood-gas partition coefficient (0.15), which indicates **fast onset** and **rapid recovery**, but not necessarily high potency. - **Potency** is determined by MAC (Minimum Alveolar Concentration), which is the concentration of anesthetic at 1 atmosphere that produces immobility in 50% of patients challenged with a surgical incision.

CNS drugs (antiepileptics, anesthetics) US Medical PG Question 10: A 75-year-old man with a seizure disorder is brought to the emergency department by a friend because of progressive confusion over the past two weeks. He is unable to provide any history. His vital signs are within normal limits. He appears lethargic and is only oriented to person. Oral mucosa is moist. There is no jugular venous distention. A basic metabolic panel shows a serum sodium concentration of 115 mEq/L but is otherwise normal. Serum osmolality is low and antidiuretic hormone level is elevated. X-ray of the chest shows no abnormalities. Which of the following is the most likely cause of this patient’s hyponatremia?

• A. Aldosterone deficiency
• B. Medication effect (Correct Answer)
• C. Low cardiac output
• D. Insulin deficiency
• E. Excess cortisol

CNS drugs (antiepileptics, anesthetics) Explanation: ***Medication effect*** - This patient's **hyponatremia** with **appropriately low serum osmolality** and **elevated antidiuretic hormone (ADH)** levels, in the absence of signs of hypovolemia or fluid overload, points to the **syndrome of inappropriate ADH secretion (SIADH)**. - Many medications, including anti-epileptic drugs like carbamazepine or oxcarbazepine (commonly used for seizure disorders), as well as selective serotonin reuptake inhibitors (SSRIs), can cause SIADH. *Aldosterone deficiency* - **Aldosterone deficiency** would likely lead to **hyperkalemia** and metabolic acidosis, which are not mentioned in the basic metabolic panel as being abnormal. - While it can cause hyponatremia due to inability to retain sodium, the elevated ADH level with normal volume status points away from primary aldosterone deficiency. *Low cardiac output* - **Low cardiac output** can lead to hyponatremia by decreased renal perfusion and activation of the renin-angiotensin-aldosterone system and ADH release. - However, this patient has **normal vital signs** and **no jugular venous distention**, making significant low cardiac output and resultant hypovolemia less likely. *Insulin deficiency* - **Insulin deficiency** (as seen in uncontrolled diabetes) typically leads to **hyperglycemia** and can cause a **pseudohyponatremia** due to osmotic effects, or true hyponatremia due to polyuria and volume depletion. - The basic metabolic panel is otherwise normal, suggesting no significant hyperglycemia or electrolyte abnormalities consistent with insulin deficiency. *Excess cortisol* - **Excess cortisol** (Cushing's syndrome) typically leads to **hyperglycemia**, hypertension, and features of fat redistribution, muscular weakness, and thin skin, none of which are detailed here. - It does not directly cause hyponatremia; conversely, cortisol has some mineralocorticoid effects and typically opposes ADH action, so severe excess would more likely cause hypernatremia or normal sodium levels.

CNS drugs (antiepileptics, anesthetics) Flashcard 1 of 10

Question: Levetiracetam is a _____ spectrum anti-epileptic

Answer: broad

CNS drugs (antiepileptics, anesthetics) Flashcard 2 of 10

Question: Benzodiazepines exert their effects via binding to an allosteric site on the _____ receptor

Answer: GABAA

CNS drugs (antiepileptics, anesthetics) Flashcard 3 of 10

Question: In addition to inhaled anesthetics, malignant hyperthermia may also be caused by _____ (muscle relaxant)

Answer: succinylcholine

CNS drugs (antiepileptics, anesthetics) Flashcard 4 of 10

Question: What type(s) of seizures (partial, tonic-clonic, or absence) may be treated with lamotrigine? _____

Answer: All three (partial, tonic-clonic, absence)

CNS drugs (antiepileptics, anesthetics) Flashcard 5 of 10

Question: Inhaled anesthetics with _____ arteriovenous concentration gradient have a faster onset of action

Answer: lower

CNS drugs (antiepileptics, anesthetics) Flashcard 6 of 10

Question: Neuro/Psych_____ administration of benzodiazepines, is useful for management of alcohol withdrawal, seizures, and anesthesia

Answer: IV

CNS drugs (antiepileptics, anesthetics) Flashcard 7 of 10

Question: carbamazepine

Answer: neural tube defects, craniofacial defects, fingernail hypoplasia, developmental delay, IUGR

CNS drugs (antiepileptics, anesthetics) Flashcard 8 of 10

Question: phenytoin

Answer: fetal hydantoin syndrome

CNS drugs (antiepileptics, anesthetics) Flashcard 9 of 10

Question: valproate

Answer: neural tube defects (inhibition of maternal folate absorption)

CNS drugs (antiepileptics, anesthetics) Flashcard 10 of 10

Question: levodopa

Answer:

Extra Information: Parkinson's diseasedopamine precursor, crosses blood-brain barrier, converted to dopamine by dopa decarboxylaseGI distress, nausea, arrhythmias, dyskinesia (on dose), akinesia (between dose)