Analgesic Drugs Flashcards
What class of drug is Ibuprofen (Nurofen, Advil, Herron Blue)?
NSAID (non-steroidal anti-inflammatory drug)
What class of drug is Aspirin (Solprin, Astrix)?
Anti-platelet analgesic
What class of drug is Paracetamol (Panadol, Panamax)?
Non-opioid analgesic
What class of drug is Celecoxib (Celebrex)?
NSAID (COX-2 selective inhibitor)
What class of drug is Diclofenac (Voltaren)?
NSAID (non-steroidal anti-inflammatory drug)
What class of drug is Indomethacin (Indocid)?
NSAID (non-steroidal anti-inflammatory drug)
What class of drug is Naproxen (Naprosyn)?
NSAID (non-steroidal anti-inflammatory drug)
What is the mechanism of action of Ibuprofen (Nurofen, Advil, Herron Blue)?
Inhibits prostaglandins (mediators of pain, inflammation and fever) by inhibiting cyclo-oxygenase (COX)
COX is the enzyme responsible for converting arachidonic acid to prostaglandin H2, which is then converted to other prostaglandins, causing pain. There are two isoforms of COX – COX-1 and COX-2
Ibuprofen is a non-selective inhibitor, meaning that it inhibits both COX-1 and COX-2
What is the mechanism of action of Aspirin (Solprin, Astrix)?
Irreversibly binds to COX-1 → prevents thromboxane A2 formation → reduced platelet aggregation
What is the mechanism of action of Paracetamol (Panadol, Panamax)?
Not fully determined.
Mechanisms involved in its analgesic effect may include inhibition of central prostaglandin synthesis and modulation of inhibitory descending serotonergic pathways.
The antipyretic effect is probably due to reduced production of prostaglandins in the hypothalamus.
Paracetamol has negligible anti-inflammatory effects.
What is the mechanism of action of Celecoxib (Celebrex)?
Have analgesic, antipyretic and anti-inflammatory actions
They inhibit synthesis of prostaglandins by inhibiting cyclo-oxygenase (COX). Inhibition of COX-2 results in anti-inflammatory and analgesic action
Although selective COX-2 inhibitors have little or no effect on COX-1 at therapeutic doses, they are still associated with GI adverse effects
What is the mechanism of action of Diclofenac (Voltaren)?
Primary mechanism responsible for its anti-inflammatory, antipyretic, and analgesic action is thought to be inhibition of prostaglandin synthesis by inhibition of cyclooxygenase (COX)
It also appears to exhibit bacteriostatic activity by inhibiting bacterial DNA synthesis
Diclofenac has a low to moderate preference to block the COX2-isoenzyme (approximately 10-fold) and is said to have, therefore, a somewhat lower incidence of gastrointestinal complaints than noted with indomethacin and aspirin
What is the mechanism of action of Indomethacin (Indocid)?
Indomethacin is a nonselective inhibitor of cyclooxygenase (COX) 1 and 2. Prostaglandins cause uterine contractions in pregnant women.
As it inhibits COX and therefore PG synthesis, indomethacin is an effective tocolytic agent, able to delay premature labour by reducing uterine contractions
In addition, it inhibits motility of neutrophils and also uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria. These additional effects also account for the analgesic and the anti-inflammatory properties
What is the mechanism of action of Naproxen (Naprosyn)?
Naproxen works by reversibly inhibiting both the COX-1 and COX-2 enzymes
What are the side effects of Ibuprofen (Nurofen, Advil, Herron Blue)?
- Active peptic ulcer disease or GI bleeding
- Nausea
- Headaches
- Dizziness
- Problems with blood clotting – increased bleeding
- Fluid and salt retention
- Hypertension
- Diarrhoea
- Can increase bronchospasm (concern for asthmatics)
- IBD may worsen
- Renal impairment
What are the side effects of Aspirin (Solprin, Astrix)?
- Gastric erosions (asymptomatic blood loss)
- Bronchospasms
- Skin rashes
- Risk of ICH
What are the side effects of Paracetamol (Panadol, Panamax)?
- Increased aminotransferases
- Hypersensitivity reactions
- Hepatotoxicity following overdose
What are the side effects of Celecoxib (Celebrex)?
- Nausea
- Dyspepsia
- GI ulceration or bleeding
- Raised liver enzymes
- Diarrhoea
- Headache
- Dizziness
- Salt and fluid retention
- Hypertension
What are the side effects of Diclofenac (Voltaren)?
- Nausea
- Dyspepsia
- GI ulceration or bleeding
- Raised liver enzymes
- Diarrhoea
- Headache
- Dizziness
- Salt and fluid retention
- Hypertension
What are the side effects of Indomethacin (Indocid)?
- Nausea
- Dyspepsia
- GI ulceration or bleeding
- Raised liver enzymes
- Diarrhoea
- Headache
- Dizziness
- Salt and fluid retention
- Hypertension
- Vertigo
What are the side effects of Naproxen (Naprosyn)?
- Nausea
- Dyspepsia
- GI ulceration or bleeding
- Raised liver enzymes
- Diarrhoea
- Headache
- Dizziness
- Salt and fluid retention
- Hypertension
What are the indications for use of Ibuprofen (Nurofen, Advil, Herron Blue)?
Administration: oral tablet, capsule, liquid
- Pain relief
- Fever relief
- Relief of swelling
- Chronic symptomatic rheumatoid arthritis and osteoarthritis
- Athletic injuries
- Acute gout
Contraindications:
Patients on low-dose aspirin
Dehydration
Asthma
Coagulation disorders
Bruising
Patients with increased CV risk
Dosage: 200-400 mg, 3 or 4 times a day for adults or 5-10mg/kg/dose, 3 or 4 times a day for children
What are the indications for use of Aspirin (Solprin, Astrix)?
Administration: oral tablet (may be dissolvable)
- Prophylaxis after MI, angina, stroke, bypass surgery
- Acute Coronary Syndrome
- Stroke prevention in AF (Warfarin)
- Artificial heart valve (to prevent emboli)
What are the indications for use of Paracetamol (Panadol, Panamax)?
Administration: oral tablet, rectal suppository, IV infusion
- Mild-to-moderate pain
- Fever
- Acute migraine (with metoclopramide)
Paracetamol may be used in all age groups and is preferred to NSAIDs for mild-to-moderate pain as it has fewer adverse effects. Adults should not take more than 8 tablets or capsules (500mg strength) per day.
What are the indications for use of Celecoxib (Celebrex)?
Administration: oral capsule
- Rheumatoid arthritis
- Osteoarthritis
- Ankylosing spondylitis
- Pain due to dysmenorrhoea or injury
Contraindications:
Heart failure
Angina
Cerebrovascular disease
Severe hepatic impairment
Risk of cardiovascular adverse events is dose-related; do not use >200mg daily long term.
What are the indications for use of Diclofenac (Voltaren)?
Administration: oral tablet, liquid, suppository, gel
- Rheumatoid arthritis
- Osteoarthritis
- Pain, especially due to inflammation (e.g. period pain)
- Local pain and inflammation in soft tissues (1% gel)
- Actinic keratoses
Contraindications:
Proctitis
Dehydration
Asthma
Coagulation disorders
Bruising
What are the indications for use of Indomethacin (Indocid)?
capsule, supporitory, injection
- Rheumatoid arthritis
- Osteoarthritis
- Pain, especially due to inflammation (e.g. period pain)
- Acute gout
- Ankylosing spondylitis
- Closure of significant patent ductus arteriosus
Contraindications:
Proctitis
Dehydration
Asthma
Coagulation disorders
Bruising
What are the indications for use of Naproxen (Naprosyn)?
Administration: oral tablet, liquid
- Rheumatoid arthritis
- Osteoarthritis
- Pain, especially due to inflammation (e.g. period pain, migraine)
- Ankylosing spondylitis
- Juvenile idiopathic arthritis
Contraindications:
Dehydration
Asthma
Coagulation disorders
Bruising
May combine with esomeprazole if high dose is being taken daily (500 mg twice daily) due to GI irritation risk.
