NEET MDS General And Dental Pharmacology, Anesthesia And General Medicine Flashcards

24 sample cards from the General And Dental Pharmacology, Anesthesia And General Medicine deck

Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.

1. Why are tetracyclines contraindicated in children under 8 and in pregnancy?

   Tetracyclines chelate calcium and deposit in developing teeth and bones, causing permanent tooth discoloration (yellow-brown), enamel hypoplasia, and impaired bone growth.

2. What is the mechanism of action and major dental relevance of fluoride?

   Fluoride promotes remineralization by forming acid-resistant fluorapatite, inhibits bacterial enolase/glycolysis, and reduces demineralization. Dental relevance: caries prevention; excess causes dental and skeletal fluorosis.

3. What is chlorhexidine and what is its main side effect with prolonged use?

   Chlorhexidine is a cationic bisbiguanide antiseptic with high substantivity used as an antiplaque/antigingivitis mouth rinse. Prolonged use causes extrinsic brown staining of teeth and tongue and altered taste.

4. Name the local hemostatic agents commonly used to control bleeding after dental extraction.

   Absorbable gelatin sponge (Gelfoam), oxidized regenerated cellulose (Surgicel), microfibrillar collagen, fibrin sealant, and topical thrombin; tranexamic acid mouthwash can also be used.

5. What is the mechanism of action of tranexamic acid?

   Tranexamic acid is an antifibrinolytic that competitively inhibits the activation of plasminogen to plasmin, thereby stabilizing fibrin clots and reducing bleeding.

6. What is the emergency drug of choice for anaphylaxis, and its dose/route?

   Epinephrine (adrenaline) 0.3-0.5 mg of 1:1000 solution intramuscularly (into the anterolateral thigh) for adults, repeated every 5-15 minutes as needed.

7. List the emergency drugs that should be available in a dental emergency kit.

   Epinephrine, oxygen, glucose (oral/IV), nitroglycerin, salbutamol inhaler, aspirin, antihistamine (diphenhydramine), hydrocortisone, and a benzodiazepine (e.g., midazolam); plus glucagon and atropine in advanced kits.

8. Describe the basic chemical structure shared by local anesthetics.

   A lipophilic aromatic ring connected via an intermediate ester or amide linkage to a hydrophilic amine group. The linkage type classifies them as esters or amides.

9. Differentiate amide from ester local anesthetics with examples and metabolism.

   Amides (lidocaine, articulate, bupivacaine, mepivacaine, prilocaine) have an '-i-' before 'caine', are metabolized in the liver, and rarely cause allergy. Esters (procaine, benzocaine, tetracaine) are metabolized by plasma pseudocholinesterase and more often cause allergy (PABA metabolite).

10. What is the mechanism of action of local anesthetics?

    They block voltage-gated sodium channels on the inner axonal membrane, preventing sodium influx and thus blocking nerve impulse generation and conduction. They act on channels in the inactivated/open state.

11. Why do local anesthetics work poorly in inflamed/infected (acidic) tissue?

    In acidic environments more of the LA exists in the ionized (charged) form, which cannot cross the lipid nerve membrane, so less of the active unionized form penetrates to block sodium channels—reducing efficacy.

12. What is the maximum recommended dose of lidocaine with and without epinephrine?

    Lidocaine without epinephrine: ~4.4 mg/kg (max ~300 mg). Lidocaine with epinephrine: ~7 mg/kg (max ~500 mg). Epinephrine slows absorption, allowing a higher safe dose.

13. Which local anesthetic is associated with methemoglobinemia?

    Prilocaine (and topical benzocaine) can cause methemoglobinemia via the metabolite o-toluidine; treated with methylene blue.

14. State the four stages of general anesthesia (Guedel's classification).

    Stage I: Analgesia (induction to loss of consciousness). Stage II: Excitement/delirium (loss of consciousness to onset of automatic breathing). Stage III: Surgical anesthesia (4 planes). Stage IV: Medullary paralysis (respiratory/cardiac arrest—overdose).

15. What does MAC (minimum alveolar concentration) measure in inhalational anesthesia?

    MAC is the alveolar concentration of an inhaled anesthetic at which 50% of patients do not move in response to a surgical stimulus; it is an index of anesthetic potency (lower MAC = higher potency).

16. Name a commonly used IV induction agent and a key advantage of propofol.

    Propofol is a common IV induction agent; advantages include rapid smooth induction, rapid recovery, and antiemetic properties. (Other IV agents: thiopental, ketamine, etomidate.)

17. What is the unique anesthetic state produced by ketamine?

    Ketamine produces 'dissociative anesthesia' (catatonia, amnesia, profound analgesia with preserved airway reflexes) by NMDA receptor antagonism; it may cause emergence hallucinations and raises blood pressure/heart rate.

18. What is conscious sedation and which level of consciousness is maintained?

    Conscious (moderate) sedation is a drug-induced depression of consciousness during which the patient responds purposefully to verbal commands, maintains a patent airway and protective reflexes, and breathes spontaneously.

19. Which agent is most commonly used for inhalational conscious sedation in dentistry, and at what concentration is it considered safe?

    Nitrous oxide (N2O) combined with oxygen; it is safe when oxygen concentration is kept at or above 30% (never less than 21%). N2O provides anxiolysis and analgesia with rapid onset/offset.

20. Which benzodiazepine is most used for IV conscious sedation and what is its reversal agent?

    Midazolam is the most commonly used IV benzodiazepine for conscious sedation (rapid onset, amnesia, short duration). Its reversal agent is flumazenil, a benzodiazepine receptor antagonist.

21. What precautions are needed for dental treatment in a patient with recent myocardial infarction?

    Defer elective dental treatment for at least 4-6 months after an MI; then use stress reduction, short appointments, supplemental oxygen, limited epinephrine in LA, and ensure nitroglycerin is available.

22. What is the recommended pre-operative blood glucose management/consideration for a diabetic dental patient?

    Treat diabetics in the morning after a normal meal and medication, avoid hypoglycemia (keep glucose source ready), ensure good glycemic control (HbA1c), and recognize that diabetics have higher infection risk and delayed healing.

23. What is the dental management concern for a patient on warfarin, and the relevant test/value?

    Warfarin increases bleeding risk; check INR before invasive procedures. Minor dental surgery is generally safe if INR is below ~3.5 (commonly within therapeutic 2-3) without stopping warfarin, using local hemostatic measures.

24. What standard precautions and considerations apply when treating a patient with a known bloodborne infectious disease such as hepatitis B or HIV?

    Apply universal/standard precautions for all patients: gloves, mask, eye protection, gown; sterilize/autoclave instruments; safe sharps handling; proper waste disposal. Patients are managed normally but with heightened vigilance against percutaneous injury; post-exposure prophylaxis protocols should be in place.

What this deck covers

General And Dental Pharmacology, Anesthesia And General Medicine flashcards FAQ