Drugs Affecting Blood and Blood Formation Practice Questions

Q: Which of the following is given with iron to increase its absorption?

Citrus fruits. **Explanation:** The absorption of oral iron occurs primarily in the duodenum and proximal jejunum. Iron is absorbed in the **ferrous (Fe²⁺) state** more efficiently than the ferric (Fe³⁺) state. **Why Citrus Fruits are Correct:** Citrus fruits are rich in **Vitamin C (Ascorbic acid)**. Vitamin C enhances iron absorption through two mechanisms: 1. It acts as a reducing agent, converting dietary ferric iron (Fe³⁺) to the more soluble ferrous iron (Fe²⁺). 2. It forms a soluble iron-ascorbate complex that prevents iron from precipitating in the alkaline environment of the small intestine. **Why Other Options are Incorrect:** * **Milk:** Contains calcium and phosphates which form insoluble complexes with iron, significantly reducing its bioavailability. * **Antacids & Alkalies:** Iron requires an acidic gastric environment to remain in its soluble ferrous form. Antacids and alkalies neutralize gastric acid, leading to the formation of insoluble iron salts, thereby inhibiting absorption. **NEET-PG High-Yield Pearls:** * **Promoters of Iron Absorption:** Ascorbic acid (Vitamin C), Gastric HCl, and amino acids (meat). * **Inhibitors of Iron Absorption:** Phytates (cereals), Oxalates (spinach), Phosphates, Carbonates, Tetracyclines, and Tannins (Tea/Coffee). * **Clinical Tip:** Patients should be advised to take iron supplements on an empty stomach with orange juice and avoid tea, coffee, or milk for at least 2 hours before and after the dose.

Q: Epogen can be given in which of the following conditions?

Anemia of chronic renal failure. **Explanation:**1. Why Option A is Correct: **Epogen (Epoetin alfa)** is a recombinant human erythropoietin (rhEPO) [1, 2, 3]. Erythropoietin is a glycoprotein hormone primarily produced by the peritubular interstitial cells of the kidney [1, 2, 3]. In **Chronic Renal Failure (CRF)**, the kidneys fail to produce sufficient erythropoietin, leading to normocytic, normochromic anemia [1, 2, 3]. Epogen acts as replacement therapy, stimulating the bone marrow to produce red blood cells, making it the treatment of choice for anemia in CRF patients [1, 3].2. Why Other Options are Incorrect:* **B. Aplastic Anemia:** This involves a primary bone marrow failure where the "factory" itself is damaged. While EPO levels are usually already high in these patients, the marrow cannot respond to it. Treatment typically requires immunosuppressants or bone marrow transplant.* **C. Hemolytic Anemia:** This is caused by the premature destruction of RBCs. The kidneys are functional and endogenous EPO levels are already maximally elevated to compensate; adding exogenous Epogen provides no benefit.* **D. Anemia of Chronic Disease (ACD):** While EPO can sometimes be used in specific cases (like cancer-related anemia), the primary pathology in ACD is iron sequestration due to high **hepcidin** levels. The first-line management is treating the underlying inflammatory condition.High-Yield NEET-PG Pearls:* **Target Hb:** When using Epogen, the target Hemoglobin should not exceed **11–12 g/dL**. Exceeding this increases the risk of hypertension, stroke, and tumor progression [1].* **Side Effects:** The most common side effect is **hypertension** and encephalopathy. It can also cause pure red cell aplasia (PRCA) due to antibody formation.* **Requirement:** For Epogen to be effective, the patient must have adequate **iron, B12, and folate stores**.* **Other Indications:** Anemia due to HIV (Zidovudine therapy) and chemotherapy-induced anemia.

Q: A patient on Warfarin has an INR of 8. What is the next best step?

Administer oral Vitamin K1.. ### Explanation The management of Warfarin-induced elevation of INR is based on the **severity of the elevation** and the **presence of bleeding**. **1. Why Option B is Correct:** According to standard guidelines (ACCP), for a patient with an **INR between 4.5 and 10 without clinically significant bleeding**, the recommended management is to omit the next few doses of Warfarin and administer **low-dose oral Vitamin K1 (Phytonadione)**. Oral administration is preferred over subcutaneous (unpredictable absorption) or intravenous (risk of anaphylaxis) routes in non-emergency settings. Vitamin K acts as a cofactor for the gamma-carboxylation of factors II, VII, IX, and X, reversing Warfarin's effect within 24–48 hours. **2. Why Other Options are Incorrect:** * **Option A:** Simply restarting at a lower dose is insufficient for an INR as high as 8, as it leaves the patient at a prolonged high risk of spontaneous hemorrhage. * **Option C:** Fresh Frozen Plasma (FFP) or Prothrombin Complex Concentrate (PCC) is indicated only in cases of **serious/life-threatening bleeding** or when immediate surgery is required, regardless of the INR. * **Option D:** Fresh blood transfusion is not the standard of care for reversing anticoagulation; it is used for volume replacement and oxygen-carrying capacity in massive hemorrhage. **3. NEET-PG High-Yield Pearls:** * **INR 10 (No bleeding):** Hold Warfarin + Higher dose oral Vitamin K (3–5 mg). * **Serious Bleeding (Any INR):** Hold Warfarin + IV Vitamin K (10 mg) + **4-factor PCC** (preferred) or FFP. * **Mechanism:** Warfarin inhibits **Vitamin K Epoxide Reductase (VKOR)**. * **Monitoring:** PT/INR is used for Warfarin; aPTT is used for Unfractionated Heparin.

Q: Which of the following substances can be used as an antidote to fibrinolytics?

Epsilon amino caproic acid. ### Explanation **Correct Option: A. Epsilon amino caproic acid (EACA)** Fibrinolytics (like Streptokinase or Alteplase) work by converting plasminogen into **plasmin**, an enzyme that degrades fibrin clots. Excessive plasmin activity can lead to severe systemic bleeding. **Epsilon amino caproic acid (EACA)** and **Tranexamic acid** act as antifibrinolytics by competitively inhibiting plasminogen activation and binding to fibrin. They occupy the lysine-binding sites on plasminogen/plasmin, preventing it from binding to and degrading fibrin, thereby stabilizing the clot and reversing the effect of fibrinolytics. **Analysis of Incorrect Options:** * **B. Protamine:** This is the specific antidote for **Heparin** overdose. It is a strongly basic protein that neutralizes acidic heparin through ionic bonding. * **C. Alteplase:** This is a recombinant tissue plasminogen activator (rt-PA). It is a **fibrinolytic agent** itself, used to dissolve clots in MI or stroke, not an antidote. * **D. Dabigatran:** This is an **oral direct thrombin inhibitor (DTI)**. Its specific reversal agent (antidote) is **Idarucizumab**. **High-Yield Clinical Pearls for NEET-PG:** * **Antifibrinolytics:** EACA and Tranexamic acid are used in fibrinolytic overdose, post-prostatectomy bleeding, and heavy menstrual bleeding. * **Tranexamic acid** is roughly 10 times more potent than EACA. * **Specific Antidotes Summary:** * **Warfarin:** Vitamin K (slow), Fresh Frozen Plasma (rapid). * **Heparin:** Protamine Sulfate. * **Dabigatran:** Idarucizumab. * **Rivaroxaban/Apixaban:** Andexanet alfa. * **Fibrinolytics:** EACA or Tranexamic acid.

Q: Which anticoagulant does not require routine coagulation profile monitoring post dosing?

Dabigatran etexilate. **Explanation:** The correct answer is **Dabigatran etexilate**. This drug belongs to the class of **Direct Oral Anticoagulants (DOACs)**. Unlike traditional anticoagulants, DOACs have a predictable pharmacokinetic and pharmacodynamic profile, a wide therapeutic window, and fixed dosing schedules. Consequently, they do not require routine laboratory monitoring (like PT/INR or aPTT) to adjust the dose. Dabigatran specifically acts as a **direct thrombin (Factor IIa) inhibitor**. **Analysis of Options:** * **Warfarin (Option A) & Phenprocoumon (Option D):** These are Vitamin K Antagonists (VKAs). They have a narrow therapeutic index and their efficacy is affected by diet, genetics, and drug interactions. They require frequent monitoring of the **International Normalized Ratio (INR)** to prevent bleeding or treatment failure. * **Argatroban (Option C):** This is a parenteral direct thrombin inhibitor used primarily in patients with Heparin-Induced Thrombocytopenia (HIT). Because it is administered intravenously and has a short half-life, it requires monitoring of the **activated Partial Thromboplastin Time (aPTT)** to ensure safe therapeutic levels. **High-Yield Clinical Pearls for NEET-PG:** * **Mechanism:** Dabigatran inhibits both free and clot-bound thrombin. * **Reversal Agent:** The specific reversal agent for Dabigatran is **Idarucizumab** (a monoclonal antibody fragment). * **Excretion:** Dabigatran is primarily eliminated by the **kidneys** (80%); thus, it is contraindicated in severe renal failure. * **Monitoring Exception:** While not routine, if monitoring is required (e.g., emergency surgery or overdose), the **Ecarin Clotting Time (ECT)** or Dilute Thrombin Time (dTT) are the most sensitive tests.

Q: Which of the following statements is not true for heparin?

Has only in vivo anticoagulant action. **Explanation:** The correct answer is **D**. Heparin is an anticoagulant that works both **in vivo** (inside the body) and **in vitro** (outside the body, such as in blood collection tubes or during dialysis). This is because heparin acts directly by activating plasma antithrombin III, which does not require a functioning physiological system to exert its effect. In contrast, oral anticoagulants like **Warfarin** act only *in vivo* because they interfere with the hepatic synthesis of clotting factors, a process that cannot occur in a test tube. **Analysis of other options:** * **Option A:** Heparin binds to **Antithrombin III (AT-III)**, inducing a conformational change that accelerates the inactivation of Thrombin (IIa) and Factor Xa by 1000-fold. * **Option B:** **Protamine sulphate** is a strongly basic protein that ionically binds to acidic heparin to form a stable, inactive complex. It is the specific antidote for heparin overdose. * **Option C:** Unfractionated Heparin (UFH) has an unpredictable dose-response; therefore, the **activated Partial Thromboplastin Time (aPTT)** is monitored to maintain a therapeutic range (typically 1.5–2.5 times the control). **High-Yield Clinical Pearls for NEET-PG:** * **LMWH (Low Molecular Weight Heparin):** Unlike UFH, LMWH mainly inhibits Factor Xa, has better bioavailability, and does **not** require routine aPTT monitoring. * **Side Effects:** The most common side effect is bleeding; the most unique is **Heparin-Induced Thrombocytopenia (HIT)**, caused by antibodies against the Heparin-Platelet Factor 4 complex. * **Safe in Pregnancy:** Heparin does not cross the placenta (due to high molecular weight and negative charge), making it the anticoagulant of choice during pregnancy.

Q: What is the drug of choice for neutropenia due to cancer chemotherapy?

Filgrastim. **Explanation:** **Filgrastim** is the drug of choice for chemotherapy-induced neutropenia [1]. It is a recombinant human **Granulocyte Colony-Stimulating Factor (G-CSF)** [1]. It works by binding to specific receptors on myeloid progenitor cells, stimulating the proliferation, differentiation, and activation of **neutrophils** [3]. By accelerating neutrophil recovery, it reduces the duration of neutropenia and the risk of life-threatening febrile neutropenia episodes [2]. **Analysis of Incorrect Options:** * **Vitamin B-12 (Cyanocobalamin):** Used to treat megaloblastic anemia caused by B12 deficiency. While B12 deficiency can cause pancytopenia, it is not the treatment for drug-induced bone marrow suppression. * **IL-11 (Oprelvekin):** This is a recombinant interleukin used specifically for **thrombocytopenia** (low platelet count). It stimulates megakaryocytopoiesis but has no significant effect on neutrophil counts [1]. * **Erythropoietin (Epoetin alfa):** This hormone stimulates the production of red blood cells (erythropoiesis). It is used for anemia associated with chronic kidney disease or chemotherapy, not for neutropenia. **NEET-PG High-Yield Pearls:** * **Sargramostim:** A recombinant **GM-CSF** (Granulocyte-Macrophage CSF) that stimulates both neutrophils and macrophages [4]. * **Pegfilgrastim:** A pegylated form of Filgrastim with a much longer half-life, allowing for once-per-chemotherapy-cycle dosing [1]. * **Common Side Effect:** The most frequent side effect of G-CSF therapy is **bone pain** (due to marrow expansion). * **Timing:** G-CSF should generally not be administered within 24 hours of chemotherapy, as it may increase myelotoxicity by stimulating rapidly dividing cells.

Question 1

Oral anticoagulants cause all except?

Accepted Answer

Anticoagulant effect both in vivo and in vitro

Answer

Interference with synthesis of vitamin K dependent clotting factors

Answer

Hematuria

Answer

Internal haemorrhage

Question 2

All of the following are irreversible ADP inhibitors except?

Accepted Answer

Cangrelor

Answer

Ticlopidine

Answer

Clopidogrel

Answer

Prasugrel

Question 3

Which of the following is given with iron to increase its absorption?

Accepted Answer

Citrus fruits

Answer

Milk

Answer

Antacids

Answer

Alkalies

Question 4

Epogen can be given in which of the following conditions?

Accepted Answer

Anemia of chronic renal failure

Answer

Aplastic anemia

Answer

Hemolytic anemia

Answer

Anemia of chronic disease

Question 5

Which of the following agents has demonstrated antithrombotic properties?

Accepted Answer

Dextran 40

Answer

Gelatin

Answer

Dextran 100

Answer

Hetastarch

Question 6

A patient on Warfarin has an INR of 8. What is the next best step?

Accepted Answer

Administer oral Vitamin K1.

Answer

Restart Warfarin at a lower dose once the INR is in the therapeutic range.

Answer

Administer fresh frozen plasma.

Answer

Transfuse fresh blood.

Question 7

Which of the following substances can be used as an antidote to fibrinolytics?

Accepted Answer

Epsilon amino caproic acid

Answer

Protamine

Answer

Alteplase

Answer

Dabigatran

Question 8

Which anticoagulant does not require routine coagulation profile monitoring post dosing?

Accepted Answer

Dabigatran etexilate

Answer

Warfarin

Answer

Argatroban

Answer

Phenprocoumon

Question 9

Which of the following statements is not true for heparin?

Accepted Answer

Has only in vivo anticoagulant action

Answer

Acts by activating anti-thrombin III

Answer

Protamine sulphate antagonizes its action

Answer

Requires aPTT monitoring in patients

Question 10

What is the drug of choice for neutropenia due to cancer chemotherapy?

Accepted Answer

Filgrastim

Answer

Vitamin B-12

Answer

IL 11

Answer

Erythropoietin

Drugs Affecting Blood and Blood Formation — MCQs

Drugs Affecting Blood and Blood Formation — MCQs

On this page

Practice by Chapter

Want unlimited practice?