B Pharmacy Important Questions Sedative And Hypnotics Important Notes
1. Sedative And Hypnotics Classification of barbiturates
- Long-acting
- Phenobarbitone
- Mephobarbitone
- Short-acting
- Pentobarbitone
- Secobarbitone
- Butobarbitone
- Ultra short-acting
- Thiopentone
- Hexobarbitone
- Methohexitone
Read And Learn More: Pharmacology Question and Answers
2. Classification of sedatives and hypnotics Newer benzodiazepine hypnotics
3. Sedative And Hypnotics Benzodiazepines
- They have a high therapeutic index
- Causes less distortion of sleep
- Do not alter the disposition of other drugs
- Lowers abuse liability
- Withdrawal symptoms are less marked
- Do not affect respiration or cardiovascular functions
4. Sedative And Hypnotics Thiopentone sodium
- It is ultra short-acting
- When injected 4 as 2.5% solution, it produces unconsciousness in 15-20 sec
- Its undissociated form has high lipid solubility and enters the brain almost instantly
B Pharmacy Important Questions Sedative And Hypnotics Long Essays
Question 1. Classify hypnotics. Mention the mechanism, actions, and management of barbiturates.
Answer:
Hypnotics Classification:
1. Hypnotics Barbiturates.
- Long-acting – Phenobarbitone
- Short-acting – Pentobarbitone.
- Ultrashort acting – Thiopentone sodium.
2. Hypnotics Benzodiazepine.
3. Hypnotics Newer hypnotics.
- Zopiclone, Zolpidem, Zaleplon.
Newer hypnotics Barbiturates:
- Barbiturates are drugs derived from barbituric acid. They are non-selective CNS depressants
Barbiturates Mechanism of Action:
Barbiturate
↓
Bind of GABAa receptor Cl- Channel complex.
↓
Potentiate GABAergic inhibition.
↓
Duration of Cl- channel kept open increases
↓
Increased chloride conductance.
↓
Membrane hyperpolarization.
↓
CNS depression.
Barbiturates Actions:
1. Barbiturates CNS.
- In hypnotic doses, barbiturates induce sleep and prolong the duration of sleep.
- Sedative doses given during the daytime can produce drowsiness, reduction in anxiety, and excitability.
- Barbiturates have anticonvulsant property.
- At higher doses, it produces general anesthesia.
2. Barbiturates Respiration.
- Depresses respiration.
3. Barbiturates CVS.
- Produces a slight decrease in BP and heart rate.
4. Barbiturates Skeletal muscles.
- Depress the excitability of the neuromuscular junction.
5. Barbiturates Kidney.
- The tone and motility of the bowel are decreased.
- Reduces urine flow
Barbiturate poisoning:
- The dosage of barbiturates above 6 -10 g causes acute barbiturate poisoning.
Barbiturate poisoning Management:
- Maintain airway, BP, adequate ventilation, and oxygen administration.
- Maintain blood volume by fluid infusion.
- Use of vasopressor.
- Gastric lavage.
- Hemodialysis is done in severe cases.
- Forced alkaline diuresis with mannitol, frusemide, or sodium bicarbonate is done.
Question 2. Describe the Barbiturate’s uses and adverse effects.
Answer:
Barbiturates:
Barbiturates Uses:
- As pre-anesthetic medication.
- As sedative and hypnotic.
- Thiopentone is used for induction of general anesthesia.
- Phenobarbitone is used in epilepsy.
- Used in the treatment of congenital non-hemolytic jaundice.
- Occasionally employed as an adjuvant in psychosomatic disorders.
Barbiturates Adverse Effects:
1. CNS effects.
- Hangover, mental confusion, impaired performed traffic accidents, distortions of mood.
2. Respiratory.
- Respiratory depression occurs.
3. Hypersensitivity.
- Skin rashes and swelling of the eyelids and lips occur.
4. Tolerance and dependence develop.
5. Withdrawal symptoms.
- Anxiety, restlessness, abdominal cramps, hallucinations, delirium, and convulsions occur.
6. Idiosyncrasy.
7. Megaloblastic anemia – due to prolong used of phenobarbitone.
Question 3. Classify barbiturates. Discuss thiopentone sodium.
Answer:
Barbiturates Classification:
1. Long-acting:
- Phenobarbitone, mephobarbitone.
2. Short-acting.
- Pentobarbitone, butobarbitone.
3. Ultra-short acting.
- Thiopentone, Hexobarbltone, Methohexltone.
Thiopentone sodium:
- Thiopentone sodium is ultra short-acting thiobarblturate
Thiopentone sodium Onset of Action:
- 15-20 sec.
Thiopentone sodium Duration of Action:
- 4 – 7 min.
Thiopentone sodium Properties:
- Highly soluble in water.
- Produces unconsciousness in 15 – 20 s.
- Produces CNS depression.
- Poor analgesic.
- Weak muscle relaxant.
- Causes respiratory depression.
- Highly lipid soluble.
- Prepared freshly before use.
- Extravasation of solution causes Intense pain, necrosis, and gangrene.
Thiopentone sodium Uses:
- Common inducing agent
- Used for short non-painful operations.
- Used to control convulsions.
- Adverse effects:
- Laryngospasm.
- Shivering.
- Deliriums
Thiopentone sodium Dose:
- Injected IV dosage – 3 – 5 mg/kg as 2 – 5% solution.
Question 4. Discuss the mechanism, actions, uses, and adverse effects of benzodiazepines.
Answer:
Benzodiazepines:
- Benzodiazepines are a group of drugs used for sedatives and hypnotics.
Benzodiazepines Mechanism of Action:
Benzodiazepines bind to the specific site on GABAa – BZD
receptors Cl- Channel complex.
↓
This potentiates the inhibitory effect of GABA.
↓
Leads to an increase in the frequency of opening of Cl Channels.
↓
Increased Cl- conductance.
↓
Membrane hyperpolarization.
↓
CNS depression.
Benzodiazepines Actions:
1. CNS actions.
- Hypnosis – increases the duration of sleep.
- Anxiolytic – reduces anxiety.
- Causes CNS depression.
- Anticonvulsant – increases the seizure threshold.
- Amnesia – produces loss of memory for the events happening after drug administration.
2. Skeletal muscle.
- Reduces muscle tone.
3. CVS action.
- At high doses, it decreases BP and heart rate.
4. GIT.
- Decreases gastric acid secretion.
5. Respiration.
- At high doses, causes respiratory depression.
Benzodiazepines Uses:
- As hypnotic – to treat insomnia.
- As anxiolytic – to reduce anxiety.
- As anticonvulsant – 4 diazepam is used.
- As a centrally-acting muscle relaxant
- As pre-anesthetic medication.
- IV midazolam or diazepam is used as an intravenous anesthetic.
- For minor procedures.
- For initial control of mania.
- During alcohol withdrawal.
- Along with analgesics, NSAIDs, spasmolytics, antiulcer, and many other drugs.
Benzodiazepines Adverse effects:
- Benzodiazepines are well-tolerated drugs.
- Common side effects are.
- Drowsiness, dizziness, vertigo, ataxia, amnesia.
- The blurring of vision.
- Dry mouth, sweating.
- Headache, daytime sedation.
- Tolerance and dependence.
- Drug given during labor causes hypotonia and respiratory depression in new-born.
Question 5. Define sedative hypnotics classify. What are the advantages of benzodiazepines over barbiturates as sedative-hypnotics?
Answer:
Definition:
Sedative:
A sedative is a drug that reduces excitement and calms the subject without inducing sleep.
Hypnotics:
Hypnotic is a drug that induces and/or maintains sleep similar to normal sleep.
Advantages of Benzodiazepine over barbiturates:
- Benzodiazepine has a high therapeutic index.
- It induces sleep similar to natural sleep.
- Hypnotic doses do not affect respiration or cardiovascular functions.
- BZDs have practically no action on another body system.
- Causes less distortion of sleep architecture.
- Do not cause microsomal enzyme induction.
- Do not alter the blood level of other drugs.
- Have low abuse liability.
- Tolerance is mild.
- Psychological and physical dependence is less marked.
- Specific BZD antagonist flumazenil is present to use in the cause of poisoning.
- The rebound phenomenon is less marked.
Sedative And Hypnotics Short Essays
Question 1. Classify barbiturates. Write it dose.
Answer:
Barbiturates:
- Barbiturates are non-selective CNS depressants.
Barbiturates Classification:
1. Long-acting.
- Phenobarbitone, mephobarbitone.
2. Short acting.
- Pentobarbitone, secobarbitone, Butobarbitone.
3. Ultra-short acting.
- Thiopentone, methohexitone, and hexobarbitone.
Barbiturates Dose:
- The dose depends on lipid solubility.
- Higher lipid solubility indicates a lower dose.
Barbituratesv Examples:
Question 2. Uses of benzodiazepines (BZDs).
Answer:
Benzodiazepines Uses:
1. As hypnotics
- BZDs are used to treat insomnia.
- They shorten sleep latency and reduce nocturnal awakening.
- In dentistry, it is used to ensure sleep the night before the dental procedure in an apprehensive patient.
2. As anxiolytics and for daytime sedation.
- Reduces anxiety.
- Produces calming effects.
3. As an anticonvulsant
- Increases seizure threshold.
- Used especially in emergency control of status epileptic- cities, febrile convulsions, tetanus, etc
4. Muscle relaxant
- BZDs reduce muscle tone by centrally acting.
- Reduces muscle tone and aches associated with anxiety.
5. As IV anesthesia.
- BZDs induce, maintain and supplement anesthetic
6. As pre-anesthetic medication.
- Used due to its sedative and anxiolytic effects.
7. During alcohol withdrawal
- Reduces the intensity of withdrawal symptoms.
- an In minor procedures like endoscopies, fracture reduction, and cardiac catheterization.
9. In psychiatry.
- For initial control of mania.
Question 3. Barbiturate poisoning.
Answer:
Barbiturate poisoning:
- The dosage of barbiturates above 6 – 10 g causes acute barbiturate poisoning.
Barbiturate poisoning Manifestations:
- Excessive CNS depression.
- Respiration depression with slow and shallow breathing.
- Hypotension.
- Bullous eruptions.
- Cardiovascular collapse.
- Renal shutdown.
- Pulmonary complications.
Question 4. Benzodiazepine as pre-anesthetic medication.
Answer:
Benzodiazepine is used for pre-anesthetic medication because it
- Reduces anxiety.
- Produces sedation.
- Produces amnesia.
- Relieves post-operative pain.
- Make anesthesia safer.
- Sraoothens induction with little respiratory depression.
- Reduces side effects of anesthesia like gastric acidity.
- Diazepam 5 -10 mg is given orally.
Sedative And Hypnotics Short Answers
Question 1. Flumazenil.
Answer:
Flumazenil is benzodiazepine antagonist
- It rarely is a benzodiazepine antagonist
- It rarely induces seizures.
- Its action starts seconds after IV administration and lasts for 1 – 2 hours.
Flumazenil Mechanism:
- It competes with BZD agonists and reverses depressant effects.
- Competes with inverse agonists for BZD receptor and reverses stimulant effects.
- It abolishes the hypnogenic, psychomotor, cognitive, and EEC effects of BZD.
Flumazenil Uses:
- To reverse actions of BZD.
- In benzodiazepine overdosage or poisoning.
Question 2. Define sedatives, hypnotics, and tranquilizers.
Answer:
Sedative:
A sedative is a drug that reduces excitement and calms the subject without inducing sleep.
Hypnotics:
Hypnotic is a drug that induces and/or maintains sleep similar to normal sleep.
Tranquilizer:
- It is an old term.
- It means a drug that reduces mental tension and produces calmness without inducing sleep or depressing mental faculties.
Question 3. Urine should be alkalized in acute barbiturate poisoning? Why?
Answer:
The dosage of barbiturates above 6 -10 g causes acute barbiturate poisoning.
- There is no specific antidote for it, only an alkaline diet- sis is the main treatment for it.
- It is done with mannitol, sodium bicarbonate, and frusemide.
- Barbiturates are weakly acidic drugs.
- But in alkaline urine, they exist in ionized form.
- Thus, they are not reabsorbed while passing through renal tubules.
- As a result, they are rapidly excreted in the urine.
Question 4. Midazolam
Answer:
- It is an ultra-short-acting benzodiazepine
- Duration of action is < 6 hours
- Dose: 7.5-10 mg
- It is used as IV anesthesia because
- It is faster
- Short-acting
- More potent
- Does not cause respiratory and CVS depression
- Does not cause pain or irritation at the injection site
- Used as an adjuvant to general anesthesia