NEET MDS Lessons
Pharmacology
Griseofulvin
- Griseofulvin is an antifungal drug. It is used both in animals and in humans, to treat ringworm infections of the skin and nails. It is derived from the mold Penicillium griseofulvum.
- It is administered orally.
Cephalosporins
Produced semisynthetically by chemical attachment of side chains to 7-aminocephalosporanic acid. Same mode of action , same resistance mech.
But tend to be more resistant than penicillins to certain beta –lactamases .
GENERATION BASED ON :
-- BACTERIAL SUSCEPTIBILITY PATTERNS
-- RESISTANCE TO BETA –LACTAMASES
--NOT EFFECTIVE AGAINST -MRSA , L. MONOCYTOGENES , C. DIFFICLE , ENTEROCOCCI
First Generation
Parentral
- CEPHALOTHIN
- CEFAZOLIN
Oral
- CEPHALEXIN
- CEPHRADINE
- CEFADROXIL
Second Generation
Parentral
CEFUROXIME
CEFOXITIN
Oral
CEFACLOR
CEFUROXIME AXETIL
Third Generation
Parentral
CEFOTAXIME
CEFTIZOXIME
CEFTRIAXONE
CEFTAZIDIME
CEFOPERAZONE
Oral
CEFIXIME
CEFPODOXIME
CEFDINIR
CEFTIBUTEN
Fourth Generation
Parentral
CEFEPIME
CEFPIROME
Celecoxib
is a highly selective COX-2 inhibitor and primarily inhibits this isoform of cyclooxygenase, whereas traditional NSAIDs inhibit both COX-1 and COX-2. Celecoxib is approximately 10-20 times more selective for COX-2 inhibition over COX-1.
Being a sulphonamide can cause skin rash & hypersensitivity rxn., occasional oedema& HT.
Indication
Osteoarthritis ( 100‐200mg BID ) , rheumatoid arthritis, dysmenorrhea, acute gouty attacks, acute musculoskeletal pain.
Pramlintide -Amylin mimetics
Mechanism
synthetic analogue of human amylin that acts in conjunction with insulin
↓ release of glucagon
delays gastric emptying
Clinical use
type I and II DM
Aspirin
Mechanism of Action
ASA covalently and irreversibly modifies both COX-1 and COX-2 by acetylating serine-530 in the active site Acetylation results in a steric block, preventing arachidonic acid from binding
Uses of Aspirin
Dose-Dependent Effects:
Low: < 300mg blocks platelet aggregation
Intermediate: 300-2400mg/day antipyretic and analgesic effects
High: 2400-4000mg/day anti-inflammatory effects
Often used as an analgesic (against minor pains and aches), antipyretic (against fever), and anti-inflammatory. It has also an anticoagulant (blood thinning) effect and is used in long-term low-doses to prevent heart attacks
Low-dose long-term aspirin irreversibly blocks formation of thromboxane A2 in platelets, producing an inhibitory affect on platelet aggregation, and this blood thinning property makes it useful for reducing the incidence of heart attacks
Its primary undesirable side effects, especially in stronger doses, are gastrointestinal distress (including ulcers and stomach bleeding) and tinnitus. Another side effect, due to its anticoagulant properties, is increased bleeding in menstruating women.
Ketoprofen
It acts by inhibiting the body's production of prostaglandin.
Serotonin-norepinephrine reuptake inhibitors(SNRIs)
e.g. venlafaxine and duloxetine
- Inhibit the reuptake of both 5-HT and norepinephrine
- Has a more favourable adverse effect profile than TCAs
Norepinephrine reuptake inhibitor
e.g. bupropion, reboxetine
Monoamine receptor antagonists
e.g. mirtazapine, trazodone, mianserin