pharmacology 2* 1

SCN9A

Gene mutation that causes Congenital Insensitivity to Pain.

Pain Treatment to Reduce Tissue Damage

The three main treatments are NSAIDs, Steroids, and Cooling.

Opioids

Treatment that acts at the spinal cord for pain management.

Mechanism of Action for Paracetamol

Inhibits the synthesis of prostaglandins.

Cyclo-Oxygenase (COX)

A group of enzymes that generate inflammatory mediators such as Prostaglandin and Thromboxane.

Adverse Effects of NSAIDs on Cardiovascular System

Altered renal function leading to fluid retention that can precipitate heart failure.

Benefits of COX2 Inhibitors

Less bleeding due to limited impact on GI tract and platelets primarily associated with COX1.

5 NSAIDs more selective for COX2

1. Ibuprofen 2) Naproxen 3) Diclofenac 4) Parecoxib 5) Celecoxib.

NSAIDs and Cardiovascular Disease

COX2 inhibitors are not recommended due to absence of antiplatelet effects, slight pro-thrombotic nature, and increased risk of MI and stroke.

Days prior to surgery to stop NSAIDs

5 days.

Effects of Weak Opioids on Cardiovascular System

1. Reduced sympathetic outflow 2) Increased vagal tone 3) Bradycardia 4) Hypotension 5) Excitation.

Effects of Weak Opioids on Respiratory System

1. Inhibits cough reflex 2) Respiratory depression.

Analgesia at the Spinal Cord

Caused by reduced pain fiber transmission to Kappa Opioid Receptors.

Analgesia at the Brainstem

Reduced pain projection to higher centers by Mu Opioid Receptors.

Reversal of Opioid Effects

Performed using Naloxone 400mcg IV, resulting in dramatic reversal of MU receptor effects.

Acute Withdrawal Effects of Opioids

1. Hypertension 2) Tachycardia 3) Tachypnea 4) Diarrhea 5) Sweating 6) Anxiety 7) Hallucinations.

Tramadol and Nefopam

Newer oral opioids.

Post Operative Morphine Patient Controlled Analgesia Procedure

Syringe driver for intermittent IV bolus, with a minimum frequency of 1mg every 5 minutes.

Treatment for Severe Chronic Pain

Oral Morphine Syrup/Tablets, Morphine SC, Diamorphine SC, and Fentanyl Transdermal Patch.

Co-Analgesics Purpose

To increase the likelihood of pain relief.

Medications effective for Chronic Neurogenic Pain

1. Gabapentin 2) Pregabalin.

Antidepressant Drugs

1. Amitryptiline 2) Duloxetine 3) Citalopram.

Peak Concentration

Maximum serum concentration that drugs achieve in a specific area of the body.

Factors Affecting Drug Distribution in the Elderly

1. Reduced lean body mass 2) Body water 3) Serum albumin 4) Kidney weight.

Effects of Reduced Lean Body Mass on Drug Distribution

Reduced volume distribution for drugs that bind to muscle (e.g., Digoxin).

Role of Albumin

Helps maintain fluid in the bloodstream and carries substances like hormones and vitamins.

Phase I Metabolism Location

Primarily occurs in the liver during modification processes.

Causes of Metabolic Changes in Phase I

1. Decreased liver blood flow 2) Decreased liver mass 3) Reduced recovery ability 4) Malnutrition 5) Diseases affecting hepatic functions.

Phase I Metabolism Outcomes

Involves oxidation, reduction, and hydrolysis; converts drugs into metabolites for excretion.

Phase II Metabolism

Conjugation that adds charged species to drugs, making them ready for excretion.

Difference between Phase I and Phase II Reactions

Phase I converts drugs to active metabolites, while Phase II forms inactive metabolites for excretion.

Age-Related Decline in Kidney Function

Creatinine clearance decreases with age; increased creatinine levels may mask renal function decline.

Effects of Analgesics on Ageing Pharmacodynamics

Increased level and duration of pain relief; drugs take longer to be expelled.

Causes of Drug-Drug Interactions

1. Absorption changes 2) Additive effects 3) Antagonizing effects 4) Metabolic changes 5) Duplication of therapies.

Risk of ACE Inhibitor and Potassium

Hyperkalemia.

Effect of Dementia on Drug Sensitivity

Increased sensitivity to drugs with CNS or anticholinergic activity, causing paradoxical reactions.

Risk of Combining Alpha Blockers and Anticholinergics

Urinary retention.

Principles of Prescribing in Elderly

Start low, titrate slow; avoid multiple new agents; assess therapeutic endpoints; manage drug interactions.

Effective Time Limit of Sedatives

Less than 2 hours; prolongation requires additional anesthetics.

What is Anxiolysis

Level of sedation where a person is relaxed but still able to respond to questions.

Drugs Available for Sedation

1. Alcohol 2) THC 3) Opiates 4) Major tranquilizers 5) Minor tranquilizers (e.g., benzodiazepines).

Example of a Minor Tranquilizer

Benzodiazepines.

What is Propofol

A short-acting medication that induces unconsciousness and amnesia; used for anesthesia and sedation.

Process of General Anaesthesia Steps

1. Induction 2) Secure airway 3) Maintenance 4) Emergence.

Types of IV General Anaesthetic

1. Propofol 2) Thiopentone 3) Ketamine 4) Etomidate.

5 Muscle Relaxants for Laryngeal Reflexes

1. Suxamethonium 2) Atracurium 3) Cisatracurium 4) Rocuronium 5) Pancuronium.

Side Effects of Muscle Relaxants

1. Depolarizing 2) Muscle pain 3) Prolonged paralysis 4) Malignant hyperthermia 5) Histamine release.

Patient Factors Causing Surgical Complications

Pre-existing conditions and past medical history influence operative risk.

Signs of Haemorrhage Post-Surgery

1. Falling blood pressure 2) Increased heart rate 3) Suction container full of blood 4) Wet swabs.

NICE Guidelines for Dental Abscess Prescription

Amoxicillin 500mg tds for 5/7 days or Penicillin V 500mg qds for 5/7 days.

Considerations Before Prescribing Antibiotics

1. Necessity 2) Site of infection 3) Organism sensitivity 4) Route of administration 5) Patient safety.

Signs of Severe Infection

Fever, lymphadenopathy, cellulitis, diffuse swelling.

Signs of Systemic Infections

Fever, malaise.

Local Tests for Isolating Pathogens

Needle aspiration of pus for lab analysis and identification of pathogens.

What is an Empiric Antibiotic?

Antibiotic prescribed based on common organisms causing an infection; initial treatment choice.

Dental Abscesses Differential Diagnoses

May not always be infectious; consider lymphadenopathy, salivary stones, mumps, and unerupted teeth.

What organism causes Pharyngitis?

S. Pyogenes (Group A Streptococcus).

What organism causes Dental Abscesses?

Viridian Group Streptococci.

Considerations about Site of Infection

pH of the site and whether the antibiotic is lipid-soluble.

Primary Resistance of Antibiotics

Some bacteria are inherently resistant to certain antibiotics.

Acquired Resistance of Antibiotics

Resistance due to mutations or gene transfer; originally sensitive bacteria become resistant.

Testing Antibiotic Sensitivity Methods

Dilution cultures, antibiotic discs, and e-tests.

Chromogenic Plates for Resistance Testing

Detect resistance through color changes produced by enzyme reactions.

Lowest MIC indicates Best Antibiotic - True or False

False; MIC is not the sole indicator for antibiotic selection.

Determining Antibiotic Dosage

Must attach to binding targets effectively, considering concentration and binding site occupancy.

Concentration Dependent Killing

Effectiveness determined by how high concentration is above the MIC.

Time Dependent Killing

Effectiveness depends on how long serum concentrations remain above the MIC.

Appropriate Treatment for Pharyngitis

Penicillin V, orally, every 6 hours for 10 days.

Antibiotics promoting Clostridium Difficile Infections

Ciprofloxacin, Clindamycin, Cephalosporins, Co-amoxiclav, and Carbapenems.