NEET MDS Lessons
Pharmacology
Ibuprofen
used to relieve the symptoms of arthritis, primary dysmenorrhoea, fever; and as an analgesic, especially where there is an inflammatory component.
Indications
rheumatoid arthritis, osteoarthritis, juvenile rheumatoid arthritis, primary dysmenorrhoea
fever, relief of acute and/or chronic pain states in which there is an inflammatory component
MOA
inhibition of cyclooxygenase (COX); thus inhibiting prostaglandin synthesis.
Paracetamol
Paracetamol or acetaminophen is analgesic and antipyretic drug that is used for the relief of fever, headaches, and other minor aches and pains.
paracetamol acts by reducing production of prostaglandins, which are involved in the pain and fever processes, by inhibiting the cyclooxygenase (COX) enzyme.
Metabolism Paracetamol is metabolized primarily in the liver. At usual doses, it is quickly detoxified by combining irreversibly with the sulfhydryl group of glutathione to produce a non-toxic conjugate that is eventually excreted by the kidneys.
Glitazones (thiazolidinediones)
Thiazolidinediones, also known as the "-glitazones"
pioglitazone
rosiglitazone
Mechanism
bind to nuclear receptors involved in transcription of genes mediating insulin sensitivity
peroxisome proliferator-activating receptors (PPARs)
↑ insulin sensitivity in peripheral tissue
↓ gluconeogenesis
↑ insulin receptor numbers
↓ triglycerides
Clinical use
type II DM
as monotherapy or in combination with other agents
contraindicated in CHF
associated with increased risk of MI (in particular rosiglitazone)
Anesthesia agents
1. Inhalation anesthetics (volatile anesthetics)
- gases : N2O, xenon
- Fluids (vaporisers)
2. Intravenous anesthetics
- Barbiturans : thiopental
- Others : propofol, etomidat
3. Pain killers
- Opioids: fentanyl, sufentanil, alfentanil, remifentanil, morphine
- Non Steroid Anti Inflamatory Drugs: ketonal, paracetamol
4. Relaxants
- Depolarising : succinilcholine
- Non depolarising : atracurium, cisatracurium, vecuronium, rocuronium
5. adiuvants
-benzodiazepins: midasolam, diazepam
Etomidate -Intravenous Anesthetics
- A nonbarbiturate anesthetic used primarily to induce surgical anesthesia.
- It does not produce analgesia.
- Etomidate has minimal effect on the cardiovascular system and respiration during induction of anesthesia.
- Like the barbiturates, etomidate decreases cerebral blood flow, cerebral metabolic rate and intracranial pressure.
- No changes in hepatic, renal or hematologic function have been reported.
- Myoclonic muscle movements are relatively common.
- Postoperative nausea and vomiting are more common with etomidate than with barbiturates.
Example calculations of maximum local anesthetic doses for a 15-kg child
Articaine
5 mg/kg maximum dose × 15 kg = 75 mg
4% articaine = 40 mg/mL
75 mg/(40 mg/mL) = 1.88 mL
1 cartridge = 1.8 mL
Therefore, 1 cartridge is the maximum
Lidocaine
7 mg/kg × 15 kg = 105 mg
2% lidocaine = 20 mg/mL
105 mg/(20 mg/mL) = 5.25 mL
1 cartridge = 1.8 mL
Therefore, 2.9 cartridges is the maximum
Mepivacaine
6.6 mg/kg × 15 kg = 99 mg
3% mepivacaine = 30 mg/mL
99 mg/(30 mg/mL) = 3.3 mL
1 cartridge = 1.8 mL
Therefore, 1.8 cartridges is the maximum.
Prilocaine
8 mg/kg × 15 kg = 120 mg
4% prilocaine = 40 mg/mL
120 mg/(40 mg/mL) = 3 mL
1 cartridge = 1.8 mL
Therefore, 1.67 cartridges is the maximum
First Generation Cephalosporins
Prototype Drugs are CEFAZOLIN (for IV use) and CEPHALEXIN (oral use).
1. Staph. aureus - excellent activity against b-lactamase-producing strains
Not effective against methicillin-resistant Staph. aureus & epidermidis
2. Streptococci - excellent activity versus Streptococcus sp.
Not effective against penicillin-resistant Strep. pneumoniae
3. Other Gm + bacteria - excellent activity except for Enterococcus sp.
4. Moderate activity against gram negative bacteria.
Caution: resistance may occur in all cases.
Susceptible organisms include:
E. coli
Proteus mirabilis
Indole + Proteus sp. (many strains resistant)
Haemophilus influenzae (some strains resistant)
Neisseria sp. (some gonococci resistant)
Uses
1. Upper respiratory tract infections due to Staph. and Strep.
2. Lower respiratory tract infections due to susceptible bacteria e.g. Strep.pneumoniae in penicillin-allergic patient (previous rash)
3. Uncomplicated urinary tract infections (Cephalexin)
4. Surgical prophylaxis for orthopedic and cardiovascular operations (cefazolin preferred because of longer half-life)
5. Staphylococcal infections of skin and skin structure