Central Nervous System Pharmacology Practice Questions

Q: All of the following are Anticholinesterases used in Alzheimer's disease except

Memantine. ***Memantine*** - While used in Alzheimer's disease, **memantine** is an **NMDA receptor antagonist**, not an anticholinesterase. - It works by blocking excessive **glutamatergic stimulation**, which is implicated in neurodegeneration. *Donepezil* - **Donepezil** is an **acetylcholinesterase inhibitor** used to treat mild to moderate Alzheimer's disease. - It increases the availability of **acetylcholine** in the synaptic cleft, improving cognitive function. *Rivastigmine* - **Rivastigmine** is a **cholinesterase inhibitor** that acts on both **acetylcholinesterase** and **butyrylcholinesterase**. - It is approved for the treatment of mild to moderate Alzheimer's disease and Parkinson's disease dementia. *Galantamine* - **Galantamine** is an **acetylcholinesterase inhibitor** and an **allosteric potentiator of nicotinic acetylcholine receptors**. - It enhances cholinergic neurotransmission and is used in the treatment of mild to moderate Alzheimer's disease.

Q: All of the following can be used for prophylaxis of migraine except

Sumatriptan. ***Sumatriptan*** - Sumatriptan is a **triptan**, a class of drugs primarily used for the **acute treatment** of migraine attacks, not for prophylaxis. - It works by constricting intracranial blood vessels and inhibiting pro-inflammatory neuropeptide release. *Topiramate* - **Topiramate** is an **antiepileptic drug** commonly used for migraine prophylaxis, especially in patients with associated epilepsy. - Its mechanism of action involves various pathways, including modulation of **GABA** and **glutamate** receptors. *Valproate* - **Valproate** (Divalproex sodium) is another **antiepileptic drug** effective in preventing migraine headaches. - It works by increasing **GABA** levels in the brain and stabilizing neuronal membranes. *Propranolol* - **Propranolol** is a **beta-blocker** widely used for migraine prophylaxis, particularly in patients with co-occurring hypertension or anxiety. - It acts by preventing cerebral vasodilation and influencing central serotonergic pathways.

Q: All of the following are effective topically except-

Procaine. ***Procaine*** - **Procaine** is an ester-type local anesthetic with poor topical penetration due to its **chemical structure and low lipophilicity**. - It is primarily used for **infiltration anesthesia** and nerve blocks, requiring direct injection into tissues to achieve its local anesthetic effects. *Amethocaine* - **Amethocaine** (tetracaine) is a potent ester local anesthetic that is very effective for **topical anesthesia**, particularly on mucous membranes and the eye. - Its high lipophilicity allows for good absorption through the skin and mucous membranes, providing prolonged anesthetic effects. *Lidocaine* - **Lidocaine** is an amide-type local anesthetic that is widely used for **topical anesthesia** due to its excellent penetration and rapid onset of action. - It is available in various forms such as creams, gels, and patches for surface anesthesia. *Cocaine* - **Cocaine** is a naturally occurring ester local anesthetic that is highly effective topically, particularly on **mucous membranes** (e.g., nasal passages). - Besides its local anesthetic properties, it also causes **vasoconstriction**, which helps to reduce bleeding.

Q: Opioid antagonist that can be given orally –

Naltrexone. ***Naltrexone*** - **Naltrexone** is an opioid antagonist used for treating **opioid dependence** and alcohol dependence. - It has good oral bioavailability and is administered orally, typically as a daily dose. *Pentazocine* - **Pentazocine** is an opioid agonist-antagonist, primarily acting as an **agonist** at kappa opioid receptors and a weak antagonist or partial agonist at mu opioid receptors. - It is not a pure opioid antagonist and thus cannot reverse opioid effects effectively. *Naloxone* - **Naloxone** is a pure opioid antagonist primarily used to reverse **acute opioid overdose** due to its rapid onset and short duration of action. - While it can be given orally, it has very **low oral bioavailability** due to extensive first-pass metabolism, making it unsuitable for chronic oral administration. *Nalbuphine* - **Nalbuphine** is an opioid agonist-antagonist, similar to pentazocine, acting as an **agonist** at kappa opioid receptors and an antagonist at mu opioid receptors. - It is typically administered parenterally for pain relief and is not used as an oral opioid antagonist.

Q: Which of the following statements about EMLA is true?

Mixture of local anesthetics. ***Mixture of local anesthetics*** - **EMLA** (Eutectic Mixture of Local Anesthetics) is a cream composed of a 1:1 mixture of **lidocaine** and **prilocaine**. - This eutectic mixture has a lower melting point than its individual components, allowing it to penetrate the skin more effectively for **topical anesthesia**. *Can be used for intubation* - EMLA is a **topical anesthetic cream** designed for skin surface application rather than mucosal surfaces or deep tissue. - Its slow onset and limited depth of penetration make it **unsuitable for intubation**, which requires rapid and profound anesthesia of the airway. *Faster acting* - EMLA requires an application time of **at least 60 minutes** (and sometimes longer for deeper anesthesia) to achieve maximal effect. - This **slow onset** is a significant limitation and is much slower than injected local anesthetics or other rapid-acting topical agents. *Used only in children* - EMLA is indeed **commonly used in children** to reduce pain from venipuncture, vaccinations, and minor procedures. - However, it is also widely used in **adults** for similar indications, such as before IV insertions, laser treatments, or skin biopsies.

Q: A young male, Farhan, suffers from a seizure disorder which is characterized by tonic rigidity of limbs followed in 20-30 seconds by tremors progressing to massive jerking of the body. This clonic phase lasts for 1-3 minutes. The anti-seizure drug of choice for this patient is:

Valproic acid. ***Valproic acid***\n- The description of tonic rigidity followed by tremors and massive jerking of the body is characteristic of a **generalized tonic-clonic seizure (GTCS)** [1], [2].\n- **Valproic acid** is a **broad-spectrum antiepileptic drug** and is considered the **drug of choice** for GTCS due to its efficacy across multiple seizure types and favorable profile for long-term management [1].\n- It is the **most commonly recommended first-line agent** for newly diagnosed GTCS in most clinical guidelines [1].\n\n*Clonazepam*\n- **Clonazepam** is a benzodiazepine primarily used for absence seizures, myoclonic seizures, and status epilepticus [1].\n- While it has broad anti-seizure activity, it is **not first-line monotherapy** for long-term management of GTCS due to concerns about **tolerance, dependence, and sedation** [1].\n\n*Ethosuximide*\n- **Ethosuximide** is **specifically indicated only for absence seizures** (petit mal seizures).\n- It has **no efficacy against tonic-clonic seizures** and would be completely inappropriate for this patient.\n\n*Fosphenytoin*\n- **Fosphenytoin** is a prodrug of phenytoin and is an effective treatment for generalized tonic-clonic seizures [1].\n- While phenytoin/fosphenytoin is a valid first-line option for GTCS, **valproic acid is generally preferred** as the drug of choice due to its **broader spectrum of activity**, better tolerability profile, and effectiveness across more seizure types [1].\n- Fosphenytoin is commonly used in both acute management (status epilepticus) and chronic therapy, but requires monitoring for side effects like gingival hyperplasia, hirsutism, and drug interactions.

Q: All of the following drugs are used in prophylaxis of migraine, except

Levetiracetam. ***Levetiracetam*** - **Levetiracetam** is an antiepileptic drug primarily used for the treatment of seizures. - It is **not indicated** or commonly used for the prophylaxis of migraine. *Propranolol* - **Propranolol** is a non-selective beta-blocker that is a well-established and effective medication for migraine prophylaxis. - It helps reduce the frequency and severity of migraine attacks. *Topiramate* - **Topiramate** is an antiepileptic drug that is also approved and widely used for migraine prophylaxis. - Its mechanism of action in migraine prevention includes modulating neurotransmitters and ion channels. *Flunarizine* - **Flunarizine** is a calcium channel blocker commonly used for migraine prophylaxis, especially in Europe and other regions. - It helps stabilize vascular tone and neuronal excitability, reducing migraine frequency.

Q: Which of the following drugs is not used in Juvenile Myoclonic Epilepsy (JME):

Carbamazepine. ***Carbamazepine*** - **Carbamazepine** is known to **exacerbate myoclonus** in patients with JME and can worsen seizures due to its mechanism of action, which can increase cortical excitability or asynchronous firing in this specific epilepsy syndrome. - Its use can **worsen seizure control** in JME, leading to more frequent or severe myoclonic jerks and generalized tonic-clonic seizures. *Zonisamide* - **Zonisamide** is a broad-spectrum antiepileptic drug that is effective in treating JME by affecting multiple pathways, including **sodium and calcium channels**, and enhancing GABAergic transmission. - It effectively **reduces myoclonic, absence, and generalized tonic-clonic seizures** typically seen in JME. *Valproate* - **Valproate** is considered a **first-line treatment** for JME due to its broad-spectrum efficacy against all seizure types associated with the syndrome (myoclonic, absence, and generalized tonic-clonic). - It works by increasing **GABA levels**, reducing neuronal excitability, and modulating sodium and T-type calcium channels. *Topiramate* - **Topiramate** is also a broad-spectrum antiepileptic drug used in JME, effective for various seizure types, including generalized tonic-clonic, myoclonic, and absence seizures. - Its mechanism involves **blocking voltage-gated sodium channels**, enhancing GABA activity, and modulating AMPA/kainate glutamate receptors.

Q: 72-year-old gentleman with normal renal functions presents with new onset focal seizures. Which of the following is the best drug to manage the patient?

Levetiracetam. ***Levetiracetam*** - **Levetiracetam** is an excellent choice for elderly patients with new-onset focal seizures due to its favorable side effect profile, **minimal drug interactions**, and lack of significant hepatic or renal metabolism, making it suitable for those with normal renal function. - It has a generally **good tolerability**, especially important in the elderly who may be on multiple medications and more sensitive to side effects. *Oxcarbazepine* - **Oxcarbazepine** can cause significant **hyponatremia**, which is a concern in elderly patients who may already be at risk due to other medications or conditions. - While effective for focal seizures, its potential for electrolyte disturbances makes it less ideal than levetiracetam in this demographic. *Sodium valproate* - **Sodium valproate** is associated with a higher risk of **cognitive side effects**, sedation, and **tremor**, which can significantly impact the quality of life in elderly patients. - It also has a potential for **hepatotoxicity** and numerous drug interactions, making it a less preferred option. *Pregabalin* - **Pregabalin** is primarily indicated for partial seizures and **neuropathic pain**, and while it can be used as an add-on therapy, it is not typically a first-line monotherapy for new-onset focal seizures. - It often causes **dizziness and somnolence**, which can increase the risk of falls in the elderly, a major concern in this age group.

Q: Shortest acting non benzodiazepine sedative is

Zaleplon. ***Zaleplon*** - Has the shortest **half-life** (approximately 1 hour) among the non-benzodiazepine hypnotics, allowing for rapid elimination. - This quick elimination makes it ideal for patients who have difficulty **falling asleep** but do not need prolonged sedation. - Particularly useful for **middle-of-the-night** dosing due to its ultra-short duration. *Eszopiclone* - Has a half-life of about 6 hours, which is significantly longer than Zaleplon. - It's the S-enantiomer of zopiclone and is used for both **sleep onset and maintenance**. - Provides more sustained sleep throughout the night compared to Zaleplon. *Zopiclone* - Has a half-life of about 5-6 hours, which is considerably longer than Zaleplon. - It's used for the short-term treatment of **insomnia** and helps both with sleep onset and maintenance. - May cause a characteristic **bitter metallic taste** as a side effect. *Zolpidem* - Has a half-life of 2-3 hours, making it longer-acting than Zaleplon. - It's commonly prescribed for problems with **sleep initiation** and occasionally for sleep maintenance. - Available in extended-release formulations for prolonged action.

Question 1

All of the following are Anticholinesterases used in Alzheimer's disease except

Accepted Answer

Memantine

Answer

Donepezil

Answer

Rivastigmine

Answer

Galantamine

Question 2

All of the following can be used for prophylaxis of migraine except

Accepted Answer

Sumatriptan

Answer

Topiramate

Answer

Valproate

Answer

Propranolol

Question 3

All of the following are effective topically except-

Accepted Answer

Procaine

Answer

Amethocaine

Answer

Lidocaine

Answer

Cocaine

Question 4

Opioid antagonist that can be given orally –

Accepted Answer

Naltrexone

Answer

Pentazocine

Answer

Naloxone

Answer

Nalbuphine

Question 5

Which of the following statements about EMLA is true?

Accepted Answer

Mixture of local anesthetics

Answer

Can be used for intubation

Answer

Faster acting

Answer

Used only in children

Question 6

A young male, Farhan, suffers from a seizure disorder which is characterized by tonic rigidity of limbs followed in 20-30 seconds by tremors progressing to massive jerking of the body. This clonic phase lasts for 1-3 minutes. The anti-seizure drug of choice for this patient is:

Accepted Answer

Valproic acid

Answer

Clonazepam

Answer

Ethosuximide

Answer

Fosphenytoin

Question 7

All of the following drugs are used in prophylaxis of migraine, except

Accepted Answer

Levetiracetam

Answer

Propranolol

Answer

Topiramate

Answer

Flunarizine

Question 8

Which of the following drugs is not used in Juvenile Myoclonic Epilepsy (JME):

Accepted Answer

Carbamazepine

Answer

Zonisamide

Answer

Valproate

Answer

Topiramate

Question 9

72-year-old gentleman with normal renal functions presents with new onset focal seizures. Which of the following is the best drug to manage the patient?

Accepted Answer

Levetiracetam

Answer

Oxcarbazepine

Answer

Sodium valproate

Answer

Pregabalin

Question 10

Shortest acting non benzodiazepine sedative is

Accepted Answer

Zaleplon

Answer

Eszopiclone

Answer

Zopiclone

Answer

Zolpidem

Central Nervous System Pharmacology — MCQs

Central Nervous System Pharmacology — MCQs

On this page

Practice by Chapter

Want unlimited practice?