HSBTE Diploma Pharmacy Pharmacology Question Ppaer and Solution. May 2019.

Subject: Pharmacology & Toxicology May 19

SECTION-A

Note: Objective type questions. All questions are compulsory (10x1=10)

• Q.1 Define Pharmacology.

• Pharmacology deals with the study of drugs, including their origin, composition, pharmacokinetics, pharmacodynamics, therapeutic uses, and potential side effects.

• Q.2 What is the Biotransformation of Drugs?

Biotransformation of drugs, (drug metabolism) chemically modifies drugs to facilitate their elimination from the body. This transformation typically occurs in the liver, although other organs may also play a role.

Note: There are two main phases of drug metabolism:

• 1. Phase I metabolism: This phase involves chemical modifications such as oxidation, reduction, or hydrolysis, primarily mediated by enzymes called cytochrome P450 (CYP) enzymes. Phase I metabolism can result in the formation of active metabolites or inactive products.

• 2. Phase II metabolism: The drug or its Phase I metabolites undergo conjugation reactions with endogenous compounds such as glucuronic acid, sulfate, glutathione, or amino acids. These conjugation reactions further increase the water solubility of the drug or its metabolites. It facilitates their excretion via urine or bile.

• Q.3 Name Adrenergic Neurotransmitter.

The adrenergic neurotransmitter in the human body is norepinephrine, also known as noradrenaline.

Note: It plays a crucial role in the sympathetic nervous system. It functions as a neurotransmitter and a hormone. It helps to regulate various physiological processes such as heart rate, blood pressure, and the "fight or flight" response. 

• Q.4 Pain-reliving medicines are known as ________

Pain-relieving medicines are known as analgesics.

Note: These medications work by acting on the central nervous system or peripheral nerves to reduce the perception of pain or inhibit the transmission of pain signals. Analgesics include various classes of drugs such as nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, and adjuvant analgesics.

• Q.5 Levodopa is used in the treatment of ________

Levodopa is primarily used in the treatment of Parkinson's disease.

Note: It is a precursor of dopamine. Dopamine is a neurotransmitter. Its deficiency occurs in Parkinson's disease. Levodopa is converted to dopamine in the brain, helping to refill dopamine levels and lessen the symptoms associated with Parkinson's disease, such as tremors, rigidity, and bradykinesia.

• Q.6 Give two side effects of Tetracyclines.

Tetracyclines are a class of antibiotics commonly used to treat bacterial infections. Two common side effects of tetracyclines include bone and teeth staining and photosensitivity to cause sunburn.

1. Bone and teeth: Tetracyclines with calcium in bone and teeth form calcium-tetracyclines chelates. This causes staining of bone and teeth. Tetracyclines deposition in bone and teeth during the growing age of children or during calcification of bone causes staining of bone and teeth, incomplete development of bone and teeth, and retard the growth of the child. Tetracyclines may get deposited in the teeth of infants if it is administered

• a. to pregnant women during mid-pregnancy or

• b. to lactating women during 4-5 months of neonates’ age or

• c. to a child at the age between 3 months and 6 years.

2. Photosensitivity: Tetracyclines make the skin more sensitive to sunlight and UV radiation. Exposure to sunlight while taking tetracyclines can result in sunburns, skin rash, or other types of skin irritation. Individuals taking tetracyclines should avoid prolonged sun exposure and use sunscreen and protective clothing when outdoors to minimize the risk of sun-related skin reactions.

• Q.7 Congestive Heart Failure.

Congestive Heart Failure (CHF) is a condition in which the heart is unable to pump blood effectively to meet the body's needs.

Note: This condition occurs when the heart muscle becomes weakened, stiff, or damaged. This leads to a decrease in the ability of the heart to contract and pump blood efficiently.

There are two main types of heart failure:

• 1. Systolic Heart Failure: This occurs when the heart muscle is unable to contract effectively during each heartbeat. This results in reduced pumping ability.

• 2. Diastolic Heart Failure: In this type, the heart muscle becomes stiff and unable to relax properly between beats, which impairs the heart's ability to fill with blood.

• Symptoms

  • 1. Shortness of breath, especially during physical exertion or when lying down

  • 2. Fatigue and weakness

  • 3. Swelling in the legs, ankles, feet, or abdomen (edema)

  • 4. Persistent cough or wheezing

  • 5. Rapid or irregular heartbeat

  • 6. Reduced ability to exercise

  • 7. Sudden weight gain due to fluid retention

• Q.8 Two examples of Autocoid.

Ans: Histamine and Prostaglandin

Note: Autocoids are locally acting substances that are produced in various tissues and organs and exert physiological effects on nearby cells or tissues. Two examples of autocoids are:

• 1. Histamine: Histamine is released by immune cells, particularly mast cells and basophils, during allergic reactions or inflammation. It acts on various target tissues, including blood vessels, the respiratory system, and the gastrointestinal tract. Histamine is involved in the regulation of vascular permeability, smooth muscle contraction such as bronchoconstriction in the lungs, and contraction of gastrointestinal smooth muscle. It stimulates gastric acid secretion.

• 2. Prostaglandins: Prostaglandins are lipid compounds derived from arachidonic acid metabolism. They are produced by various cells in response to injury, inflammation, or other stimuli. Prostaglandins cause inflammation, regulation of smooth muscle contraction (e.g., in the uterus during labor), mediation of pain sensation, and modulation of blood pressure and blood clotting. Nonsteroidal anti-inflammatory drugs (NSAIDs) work by inhibiting the synthesis of prostaglandins, thereby reducing inflammation and pain.

• Q.9 Write two uses of Diuretics.

Ans: To treat hypertension and edema.

Note: Diuretics are medications that increase the production of urine by the kidneys. They are commonly used to treat various medical conditions such as

• 1. Hypertension (High Blood Pressure): Diuretics are frequently prescribed as part of the treatment regimen for hypertension. Diuretics help to reduce the volume of blood by increasing water excretion. This in turn lowers blood pressure. They are often used alone or in combination with other antihypertensive medications to achieve optimal blood pressure and reduce the risk of cardiovascular complications associated with high blood pressure.

• 2. Edema (Fluid Retention): Diuretics are also used to manage edema, which is the abnormal accumulation of fluid in the body's tissues. Diuretics help to remove excess fluid from the body by increasing urine output.

• Q.10 Angina Pectoris.

Chest pain or discomfort that occurs when the heart muscle doesn't receive enough oxygen-rich blood is called angina pectoris. Angina is described as a pressure, squeezing, heaviness, or tightness in the chest. It may also be felt in the shoulders, arms, neck, jaw, or back.

Note: Angina pain can be triggered by physical exertion, emotional stress, exposure to cold temperatures, heavy meals, or other factors that increase the heart's workload.

There are different types of angina:

• 1. Stable Angina: It occurs during physical activity or emotional stress and resolves with rest or medication. The pattern of symptoms is usually predictable and consistent over time.

• 2. Unstable Angina: Unstable angina is more serious and unpredictable than stable angina. It occurs at rest or with minimal exertion and may not be relieved by rest or medication. Unstable angina is considered a medical emergency as it signals a future heart attack.

• 3. Variant Angina: This type of angina is caused by a temporary spasm of the coronary arteries, leading to reduced blood flow to the heart muscle. It occurs at rest and can be associated with certain triggers, such as smoking or exposure to cold temperatures.

SECTION-B

Note: Very short answer type questions. Attempt five questions out of seven questions. 5x3=15

• Q.11 Give advantages of the oral route of administration.

The oral route of administration, which involves taking medications by mouth, offers several advantages:

• 1. Ease of Administration: Oral medications are easy to administer. They do not require specialized equipment or medical personnel for administration. It is suitable for self-administration at home.

• 2. Painless Administration: Injections cause discomfort or pain. Oral medication is painless and well-tolerated by most patients.

• 3. Patient Compliance: Higher rates of patient compliance compared to other routes such as injections or intravenous infusions. This leads to better treatment outcomes.

• 4. Variety of Formulations: Oral medications are available in a wide range of formulations, including tablets, capsules, liquids, powders, and chewable tablets. This variety allows for flexibility in dosing and administration as per patient preferences and needs.

• 5. Cost Effective: oral medication dosage forms have lower production costs and do not require specialized equipment or medical supervision for administration. This reduces overall healthcare expenses.

• 6. Improved Safety Profile: The oral route is considered safer than injections or infusions. The parenteral route carries a higher risk of infection, tissue damage, or other adverse events. Oral medications are absorbed slowly into the bloodstream. This allows better control of drug levels and minimizes the risk of sudden rises or drops in drug concentration.

• 7. Versatility: Many medications can be administered orally, including drugs for a wide range of medical conditions such as infections, cardiovascular diseases, diabetes, pain management, and psychiatric disorders. This versatility makes the oral route suitable for treating a variety of illnesses and conditions. 

• Q.12 What are Narcotic Analgesics? Give Examples.

Narcotic analgesics, also known as opioids or opiates relieve moderate to severe pain. They work by binding to receptors in the brain and spinal cord to reduce the perception of pain. Examples of narcotic analgesics include:

• 1. Morphine: Morphine is one of the most potent and effective opioid analgesics. It is commonly used to manage severe pain, such as that experienced after surgery, trauma, or in cancer patients

• 2. Codeine: .Codeine is a less potent opioid analgesic to treat mild to moderate pain and suppress cough.

• 3. Fentanyl: Fentanyl is a synthetic opioid analgesic that is more potent than morphine. It is commonly used in for pain management, particularly during surgical procedures or in the management of severe, chronic pain.

• 4. Methadone: Methadone is a synthetic opioid analgesic useful for managing chronic pain and opioid addiction. It is used as part of medication-assisted treatment (MAT) for opioid dependence and is also prescribed for chronic pain management.

• Q.13 Classify Antiarrhythmic Agents.

Antiarrhythmic agents are medications used to treat abnormal heart rhythms (arrhythmias). These medications work by stabilizing the electrical activity of the heart, either by suppressing abnormal electrical impulses or by regulating the heart rate. Antiarrhythmic agents can be classified into different classes based on their mechanism of action and effects on cardiac ion channels. The Vaughan-Williams classification system is commonly used to categorize antiarrhythmic drugs into four main classes:

• 1. Class I Antiarrhythmics: These drugs act by blocking sodium channels in cardiac cells. They reduce the rate of depolarization and impulse conduction. Class I agents are further subdivided into three subclasses based on their effects on the duration of the action potential (impulse):

  • a. Class IA: Drugs in this subclass prolong the action potential (impulses) duration and refractory period. Examples include quinidine, procainamide, and disopyramide.

  • b. Class IB: Drugs in this subclass shorten the action potential (impulses) duration and refractory period. Examples include lidocaine, mexiletine, and phenytoin.

  • c. Class IC: Drugs in this subclass have minimal effects on action potential (impulses) duration but significantly slow conduction velocity. Examples include flecainide, propafenone, and moricizine.

• 2. Class II Antiarrhythmics: These drugs are beta-blockers that work by blocking beta-adrenergic receptors in the heart, thereby reducing sympathetic stimulation and heart rate. Examples include propranolol, metoprolol, and atenolol.

• 3. Class III Antiarrhythmics: These drugs act by blocking potassium channels. This leads to increased repolarization time and an effective refractory period, preventing reentry arrhythmias. Examples include amiodarone, sotalol, and dofetilide.

• 4. Class IV Antiarrhythmics: These drugs are calcium channel blockers that act by blocking calcium channels in cardiac cells, thereby reducing calcium influx and slowing conduction. This results in a decrease in heart rate and conduction velocity. Examples include verapamil and diltiazem.

• Q.14 Write a Short Note on Antacids.

Antacids are agents used to neutralize stomach acid to provide relief from discomfort associated with excess acid in the stomach. Discomforts associated with excess acid in the stomach are symptoms of acid reflux, heartburn, peptic ulcer, and indigestion. They are more effective in stomach-containing food than an empty stomach. Food content delays the emptying time of antacids.

Classification: Antacids are classified into the following two classes depending upon their mode of action

• 1. Systemic Antacids: Sodium bicarbonate

• 2. Non-Systemic Antacids:

  • a. Calcium-containing antacids: calcium carbonate

  • b. Aluminium contains antacids aluminum hydroxide,

  • c. Magnesium Containing Antacids: magnesium hydroxide,

  • d. Combination Antacids: Various antacid combinations are available in the market.

    • · Combination of rapid-acting magnesium hydroxide and slow-acting aluminum hydroxide.

    • · Magaldrate: Magaldrate is a hydroxymagnesium aluminate complex.[Mg(OH)2 and Al(OH)2]. It is poorly absorbed and thus provides sustained antacid action.

    • · Addition of simethicone and methyl polysiloxane to antacid. They have antiflatulence action.

    • · Addition of seaweed alginate to antacid. It makes mucous viscous. Viscous mucous makes a coat on the GIT mucosa. It is most effective in a patient suffering from gastroesophageal reflux.

    • Antacids are divided into the following two groups, depending on the rate of absorption:

• · Fast Acting Antacids: Sodium bicarbonate, Magnesium oxide, Magnesium hydroxide, Magnesium carbonate

• · Slow Acting Antacids: Aluminium Hydroxide, Magnesium Trisilicate.

• Q.15 Adverse effects of Penicillin.

• The following are some adverse effects of penicillin:

• a. Allergic reactions: This is the most serious adverse effect of penicillin. Allergic reactions can range from mild skin rashes and itching to severe anaphylaxis. Anaphylaxis is a life-threatening allergic reaction that requires immediate medical attention.

• b. Cross-reactivity with other antibiotics: Some individuals who are allergic to penicillin may also experience allergic reactions to other antibiotics in the beta-lactam class, such as cephalosporins.

• c. Skin reactions: In addition to allergic reactions, penicillin can cause non-allergic skin rashes, hives, or itching. These reactions are usually mild and resolve on their own once the medication is stopped.

• d. Gastrointestinal issues: Nausea, vomiting, diarrhea, and abdominal pain. These symptoms are usually mild and temporary.

• e. Rare but serious effects: In rare cases, penicillin can cause more serious adverse effects such as severe diarrhea kidney damage, liver problems, and blood disorders.

• f. Yeast infections: Penicillin can disrupt the natural balance of bacteria in the body. This leads to an overgrowth of yeast (Candida). This can cause infections such as oral thrush or vaginal yeast infection. 

• Q.16 Enlist various classes of Diuretic agents.

Diuretics promote the increased production of urine. This helps the body to excrete water and salt. There are several classes of diuretic agents, each with different mechanisms of action. The following are the main classes of diuretics along with examples:

• a. Thiazide Diuretics: Examples: Hydrochlorothiazide, Chlorthalidone, Indapamide

• Mechanism of action: Thiazide diuretics inhibit sodium reabsorption in the distal convoluted tubules of the kidneys. This leads to increased excretion of sodium and water. They are commonly used to treat hypertension and mild to moderate edema.

• b. Loop Diuretics: Examples: Furosemide (Lasix), Bumetanide, Torsemide

• Mechanism of action: Loop diuretics inhibit sodium-potassium-chloride cotransporters in the thick ascending loop of Henle. This leads to significant sodium and water loss. They are potent diuretics and are used to treat severe edema and conditions such as heart failure and acute kidney injury.

• c. Potassium-Sparing Diuretics: Examples: Spironolactone, Eplerenone, Amiloride, Triamterene

• Mechanism of action: Potassium-sparing diuretics either antagonize the effects of aldosterone (aldosterone antagonists) or directly inhibit sodium channels in the collecting ducts of the kidneys. These diuretics promote diuresis while minimizing potassium loss. They are used in combination with other diuretics.

• d. Osmotic Diuretics: Examples: Mannitol, Glycerin

• Mechanism of action: Osmotic diuretics are non-absorbable substances that increase the osmotic pressure of the glomerular filtrate, leading to the retention of water in the nephron and increased urine production. They are used to reduce intracranial pressure, and intraocular pressure, and to prevent acute kidney injury in certain situations.

• e. Carbonic Anhydrase Inhibitors: Examples: Acetazolamide, Dorzolamide (topical)

• Mechanism of action: Carbonic anhydrase inhibitors inhibit the enzyme carbonic anhydrase, Carbonic anhydrase plays a role in bicarbonate reabsorption in the proximal convoluted tubules of the kidneys. This leads to increased excretion of bicarbonate, sodium, and water. These diuretics are used to treat glaucoma, altitude sickness, and metabolic alkalosis.

• Q.17 Write short notes on Antihistamines.

Antihistamines are used to relieve symptoms associated with allergic reactions, such as itching, sneezing, runny nose, and hives. They work by blocking the effects of histamine released by the body in response to allergens. Antihistamines are classified into two main categories: first-generation and second-generation.

• 1. First-generation antihistamines: Examples include diphenhydramine, chlorpheniramine, and hydroxyzine.

• Mechanism of action: These antihistamines are relatively sedating because they can cross the blood-brain barrier and exert effects on the central nervous system. They work by blocking histamine receptors, primarily H1 receptors. This reduces allergic symptoms.

• Uses: To relieve symptoms of allergic reactions, motion sickness, and insomnia, and as adjunctive therapy for anaphylaxis.

• Side effects: Sedation, drowsiness, dizziness, dry mouth, blurred vision, constipation, and urinary retention. These side effects are due to their ability to cross the blood-brain barrier and affect the central nervous system.

• 2. Second-generation antihistamines: Examples include cetirizine, loratadine, fexofenadine, and desloratadine.

• Mechanism of action: Second-generation antihistamines are less sedating because they have limited ability to cross the blood-brain barrier. This results in fewer central nervous system effects. They selectively block H1 receptors in peripheral tissues, providing relief from allergic symptoms without causing significant sedation.

• Uses: To treat allergic rhinitis (hay fever), allergic conjunctivitis, chronic urticaria (hives), and other allergic conditions.

• Side effects: Second-generation antihistamines are generally well-tolerated. However, they can still cause mild side effects such as headache, dry mouth, and fatigue in some individuals. These side effects are less common compared to first-generation antihistamines.

Alok Bains