Meloxicam and Celecoxib is a preferential COX-2 inhibitor
Methotrexate is actively secreted by organic anion transporters (OAT1/OAT3) in the renal proximal tubular cells
Epileptogenic Anesthetic: Enflurane
Most Pungent Inhalational Agent: Desflurane
Increases Cerebral Blood Flow (CBF): Halothane
Light-Sensitive Anesthetic: Halothane
Decreases Hepatic Blood Flow:Halothane
Prodrug
A prodrug is a pharmacologically inactive (or weakly active) compound that is converted into an active, functional drug inside the body after administration.
Enalapril - converted by liver enzymes to Enalaprilat (ACE inhibitor for hypertension).
Levodopa - crosses the blood-brain barrier and converts to Dopamine in the brain (for Parkinson's disease).
Codeine - metabolized by the liver into Morphine (pain relief).
Valacyclovir - converted to Acyclovir (antiviral with significantly higher oral bioavailability).
Drugs in pregnancy
Medication safety depends on the drug, dose, duration, trimester and maternal condition.
Drug/exposure
High-yield concern
ACE inhibitors/ARBs
Fetal renal toxicity, especially later in pregnancy
Warfarin
Fetal harm and bleeding risk
Isotretinoin
Major teratogenicity
Valproate
Neural tube defects and neurodevelopmental risks
Tetracyclines
Developing tooth discoloration and effects on mineralizing tissues
Methotrexate
Embryotoxicity and teratogenicity
NSAIDs
Fetal renal dysfunction/oligohydramnios from 20 weeks; additional ductus arteriosus risk later
Lithium
Requires careful risk–benefit assessment and monitoring
Phenytoin
Fetal hydantoin syndrome risk
Analgesics in pregnancy
Drug
General exam point
Paracetamol
Usually preferred when an analgesic is needed
NSAIDs
Avoid from 20 weeks unless specifically advised; avoid at 30 weeks and later
Aspirin
Low-dose aspirin may be prescribed for specific obstetric indications
Opioids
Use only when indicated, with individualized risk assessment
Antibiotics during lactation
Your source highlights several drugs that require caution during breastfeeding. These are not all absolute contraindications; current recommendations depend on the particular drug and infant.
Drug/class
High-yield consideration
Tetracyclines
Avoid prolonged or repeated courses when safer alternatives are appropriate
Chloramphenicol
Generally avoided when alternatives are available
Fluoroquinolones
Assess the specific agent and clinical indication
Sulfonamides
Caution with premature, jaundiced or ill infants and those at risk of G6PD-related hemolysis
Metronidazole
Recommendations vary with dose and regimen
Clindamycin
Monitor for infant diarrhea or candidiasis when used
Safe alternatives
The source lists commonly used options such as penicillins, cephalosporins and selected macrolides, depending on the infection and patient circumstances.
Dental exam tip: Tetracyclines are the classic drug associated with discoloration of developing teeth. Permanent teeth are particularly vulnerable during mineralization in childhood.
LAST-MINUTE FCPS RECALL
Pharmacokinetics and pharmacodynamics
MCQ clue
Answer
IV bioavailability
100%
Low Vd
Drug largely remains in plasma
High Vd
Extensive tissue distribution
Time to near steady state
Approximately 4–5 half-lives
Loading dose
Determined mainly by Vd and target concentration
Maintenance dose rate
Determined mainly by clearance
Zero-order elimination
Constant amount eliminated per unit time
Potency
Dose/concentration required for effect
Efficacy
Maximum effect
Competitive antagonist
Usually surmountable by increasing agonist
Noncompetitive antagonist
Reduces maximal response
Therapeutic index
TD₅₀/ED₅₀
Autonomic pharmacology
MCQ clue
Answer
α₁
Vasoconstriction
α₂
Reduced presynaptic transmitter release
β₁
Increased heart rate and contractility
β₂
Bronchodilation
M₂
Reduced heart rate
M₃
Glandular secretion and smooth-muscle contraction
Anaphylaxis
IM epinephrine
Organophosphate poisoning
Atropine + pralidoxime when indicated
Anesthesia
MCQ clue
Answer
Local anesthetic mechanism
Voltage-gated sodium-channel blockade
Malignant hyperthermia
Dantrolene
Propofol
Hypotension and respiratory depression
Ketamine
NMDA antagonism; dissociative anesthesia
Etomidate
Adrenal steroid suppression
Succinylcholine
Depolarizing neuromuscular blocker
Rocuronium reversal
Sugammadex in appropriate settings
Local anesthetic systemic toxicity
Consider lipid emulsion therapy
Cardiovascular and renal pharmacology
MCQ clue
Answer
ACE inhibitor adverse effect
Cough, hyperkalemia, angioedema
Spironolactone
Hyperkalemia, gynecomastia
Loop diuretic
Increased urinary calcium
Thiazide
Reduced urinary calcium
Amiodarone
Pulmonary, thyroid and hepatic toxicity
Adenosine
Transient AV nodal blockade
Warfarin monitoring
INR
Heparin reversal
Protamine
Dabigatran reversal
Idarucizumab
PDE-5 inhibitor + nitrate
Severe hypotension
Antibiotics
MCQ clue
Answer
β-lactams
Inhibit cell-wall synthesis
Aminoglycosides
30S; nephrotoxicity and ototoxicity
Tetracyclines
30S; tooth discoloration
Macrolides
50S; QT/interactions
Clindamycin
C. difficile colitis
Rifampin
RNA polymerase inhibition; enzyme induction
Isoniazid
Mycolic acid synthesis inhibition; give B6 when indicated
