STENCILDENT

                PARACETAMOL Analgesic ,anti-pyretic ,week anti inflammatory properties. Brain:Active cyclo-oxygenase -anti-pyretic action Gastric irritation mild STUDENT CORNER: HI!my dear stencildent family welcome back to our website ,if your knew to our site please do consider checking out our other posts to ,now moving on to our topic of discussion for today its about a very well and often used,and misused drug paracetamol it belongs to non -steroidal antiinflammatory drug click on this link to learn about  NSAID CLASSIFICATION  . PHARMACOKINETICS: Orally well absorbed Thirty percent protein bound Metabolised by microsomal enzyme  ADVERSE EFFECT: Nausea Rashes Large dose:  Acute paracetamol poisoning  Hepatotoxic Jaundice Nephrotoxicity - renal failure USES: Analgesic:tooth ache ,head ache  Antipyretic Chronic pulpitis,periodontal abscess,post extraction MECHANISM OF ACTION: Small portion: metabolised to -N-acetyl benzoquinone gets detoxified ,conjugation to glutathione large doses

                       METRONIDAZOLE INTRODUCTION: Antiameobic drug useful in infection caused by protozoa Entamoeba histolytica Its a tissue amoebicidal used for both extraintestinal and intra intestinal amoebiasis Metronidazole belongs to class nitroimidazole which is the first line drug for all forms of amoebiasis They are active against other protozoa ( TRICHONOMAS VAGINALIS, GIARDIA LAMBIA AND ANEROBIC INFECTION) MECHANISM OF ACTION: Metronidazole as a pro drug enter in the organism  Nitro group present in the drug accept electron from ferredoxin  Nitro group converted to highly reactive nitro radical Highly reactive nitro radical damage microbial DNA  Leads to death of organism produce cidal effects PHARMACOKINETICS: ABSORPTION: Orally ,Intravenous, Topical  DISTRIBUTION: Diffuse into tissue METABOLISM: liver EXCRETION: Urine  ADVERSE EFFECT : GASTROINTESTINAL :Nausea,vomiting ,abdominal cramps ALLERGIC REACTION: skin rashes -urticaria ,flushing  CENTRAL NERVOUS SYSTEM : ataxia,d

                              ODONSETRON  Pro type of anti-emetic drug Controls cancer chemotherapy /radiotherapy ,drug induced vomiting. MECHANISM OF ACTION: It blocks depolarization of 5 HT through 5-HT3 receptor on vagal  afferent in gastro intestinal tract. Cytotoxic drugs/chemotherapy causes cellular damage there by induce vomiting ,thereby release of mediator of 5-HT from intestinal mucosa,activation of vagal afferent in gut and sends emetogenic impulse to NTS. Odonsetron blocks emetogenic impulses both at peripheral and central relay  PHARMACOKINETICS: Oral bio availability :60-70% Eliminated in urine ,faceces SIDE EFFECTS : Headache Mild constipation Rashes  Allergic reaction  CONCLUSION: Hi stencildent family hope you all liked this short notes on odonsetron if it helped you learn then do let me know in the comment section below as this would motivate me to post more such content .                                   Thank you  NOTE: pharmacology notes are for purely educational

  NON -STEROIDAL INFLAMMTORY DRUG STUDENTS CORNER: Hello VANAKKAM!,my dear stencildent family members this is a continuation of previous blog on introduction to non-steroidal anti inflammatory drug where in we learnt classification, mechanism of action of NSAID in detail along with a short notes on ASPIRIN if we haven't learnt about it yet then do click on the link to  NSAID -PART 1 learn more. Now lets get inside our content on propionic acid derivative drug-ibuprofen ,acetic acid derivative drug -ketorolac and fenamate derivative mephenamic acid.  PROPIONIC ACID DERIVATIVE : IBUPROFEN Better tolerated alternative to aspirin ,safest NSAID  Antiplatelet  action is short lasting  Weaker anti-inflammatory drug USES: Analgesic ,anti-pyretic Rheumatoid arthritis Tooth extraction(aspirin +codeine) Soft tissue injury ADVERSE EFFECTS : Nausea Vomiting CENTRAL NERVOUS SYSTEM: Headache ,dizziness, blurring of vision ,rash ,itching  PHARMACOKINETICS AND INTERACTION: ABSORPTION-Well absorbed

  NON -STEROIDAL ANTI INFLAMMATORY DRUG  They are non-opioid analgesics  They have anti-pyretic ,uricosuria properties CLASSIFICATION  A)NON SELECTIVE COX-INHIBITOR : ACETIC ACID ACID :   KETOROLAC,INDOMETHACIN,NABUMETONE ENOLIC ACID : PIROXICAM PYRAZOLONE : PHENYLBUTAZONE OXYPHENBUTAZONE FENAMATE : MEPHENAMIC ACID PROPIONIC ACID : IBUPROFEN KETOPROFEN NAPROXEN FLURBIPROFEN SALICYLATE: ASPIRIN B)PREFERENTIAL COX-2 INHIBITORS  : DICLOFENAC ACECLOFENAC ETODOLAC NIMESULIDE MELOXICAM C)SELECTIVE COX - 2 INHIBITOR : PARECOXIB CELECOXIB ETORICOXIB D)ANALGESICS WITH ANTI-PYRETIC WITH POOR ANTI-INFLAMMATORY ACTION: PARA AMINOPHENOL DERIVATIVE :PARACETAMOL (ACETAMINOPHEN) PYRAZOLONE DERIVATIVES:METAMIZOL PROPIPHENAZONE BANZOXAZOCINE DERIVATIVE :NEFOPAM MECHANISM OF ACTION: When any infectious agent (stimuli)enters the  body it affect phospholipid bilayer ( important component of cell membrane)it stimulate enzyme phospholipase A2  ,it destroys phospholipids to arachidonic acid it enters two path

                         CIPROFLOXACIN Its a first generation fluoroquinolones anti microbial drug Active against gram negative bacilli especially Enterobacteriaceae and Neisseria Its highly susceptible to salmonella ,shigella, Enterobacter Rapid bactericidal activity activity by digesting DNA It has low frequency of resistance MECHANISM OF ACTION: Fluoroquinolone does 2 roles :  Inhibit topoisomerase in gram positive bacteria ,there by inhibit separation of DNA Strands  Inhibit DNA Gyrase enzyme in gram negative bacteria ,thereby resealing strands of DNA  Ultimately both block synthesis of bacterial DNA and produce bactericidal effect. PHARMACOKINETICS: ABSORPTION: Oral, Intravenous ,topical  DISTRIBUTION: Kidney ,lung ,bile METABOLISED: Liver  EXCRETION: Urine USE: Anthrax Bacterial diarrhea Chancroid Conjunctivitis Typhoid fever : first choice Tuberculosis: component for chemotherapy Urinary tract infection : upper urinary tract infection ADVERSE EFFECTS : GASTROINTESTINAL TRACT: Na

  RIFAMPICIN : Its a semi-synthetic derivative of Rifamycin  1st line drug used in tuberculosis  Rifampicin is bactericidal to M.tuberculosis,M.leprae Inhibits most gram positive and gram negative bacteria like staphylococcus aureus,N.meningitidis,E.coli,klebsiella,pseudomonas,proteus and legionella ANTI-TUBULAR ACTION: Tuberculocidal :treatment for tuberculosis  Acts on intra and extracellular organism and drug resistant organism hence called - STERILISING AGENT  Inhibit DNA dependent RNA synthesis if used alone it develops drug resistance                                                    Rifampicin             Bind with beta subunit of DNA dependent RNA polymerase                                          Inhibition of MRNA synthesis                                            Tuberculocidal effect PHARMACOKINETICS: 1)ABSORPTION:Given orally 2)DISTRIBUTION:Penetrate cavities,caseous masses,placenta and meninges 3)METABOLISM :Liver 4)EXCRETION:Bile and urine  T 1/2 : 2 hours  INTERACT

  LOCAL ANAESTHETICS Drugs that block peripheral nervous tissue when applied locally to nerve tissue in appropriate concentration,without loss of consciousness CLASSIFICATION: A) INJECTABLE : SHORT ACTING : Procaine  Chloroprocaine  INTERMEDIATE ACTING  Lignocaine  Prilocaine LONG ACTING Bupivacaine  Ropivacaine tetracaine  B) SURFACE ANAESTHETIC: Lignocaine  Cocaine Tetracaine MECHANISM OF ACTION : Primary mechanism of action: blockade of voltage gated sodium channel  local anaesthesia diffuse through cell membrane to bind the voltage sensitive sodium channel to prevent generation of action potential and conduction  DIFFERENTIAL BLOCKADE: 1)Autonomic (1st blocked )followed by sensory fibres,pain temperature ,touch ,pressure,vibration  Non myelinated fibres are blocked readily than myelinated  FEATURES OF LOCAL ANAESTHETICS: 1) It should have quick onset of action  2)It should not be irritating to skin and mucous membrane  3)Duration of action must be long enough to allow desired surge

  CATECHOLAMINES Neurotransmitter that take part in adrenergic transmission Catecholamines are synthesised from adrenal medulla ,from a specialised cell:chromaffin cell  The catecholamine includes : Adrenaline Nor -adrenaline Dopamine SYNTHESIS : 1)AT BLOOD : Phenylalanine 

ANGIOTENSIN CONVERTING ENZYME INHIBITOR COVID -19 (CORONAVIRUS 2019 DISEASE)a current pandemic infection caused by   RNA virus  Its mainly transmitted by droplet generated when an infected person coughs,sneezes or inhales. Symptoms:fever ,dry cough,tiredness.  Less common symptoms :headache,sore throat,diarrhoea,loss of taste or smell. Even if you notice mild symptoms don't hesitate to ask your doctor.  Get vaccinated at your chance  Getting vaccinated is very important to save us as well as your close ones , to learn more about herd immunity and its importance do check it out through this link  HERD IMMUNITY ANGIOTENSIN CONVERTING ENZYME INHIBITOR CAPTOPRIL: Dipeptide ace inhibitor Orally active Prototype drug Sulfhydryl containing dipeptide surrogate of proline  Abolish pressor action of angiotensin 1 without affecting angiotensin 2 Increase plasma kinin level : responsible for cough ,angioedema,hypotensive action. Decrease blood pressure is seen more in sodium depleted subject a

  PROTON PUMP INHIBITOR  Peptic ulcer occurs due to the imbalance between acid -pepsin secretion and mucosal defense factor  Proton pump inhibitor act by inhibiting the gastric acid secretion  Its a efficacious inhibitor omeprazole is a drug that's commonly use MECHANISM OF ACTION: The parietal cells of stomach secrete :H + with the help of enzyme H+K+ATPase present in the plasma membrane Omeprazole and other proton pump inhibitor are produrg get activated in the acidic environment of the stomach to sulfenamide which binds covalently with H+K+ATPase   The binding is irreversible Single dose can almost (95%)inhibit gastric secretion Acid secretion start only after new H+K+ATPase enzyme is synthesises . Ulcer heals rapidly even in resistant cases. PHARMACOKINETICS; Given as enteric coated granules to avoid degradation by acid in stomach Effect of 1 dose remains for 2 to 3 days Microsomal enzyme inhibitor Increases level of benzodiazepine,warfarin  ADVERSE EFFECT : Headache Nausea Pai

  PEPTIC ULCER  - Part 1  Peptic ulcer is result from imbalance between acid pepsin secretion and mucosal defense factor Stomach secrete 2.5 litre of gastric juice daily MECHANISM OF ACTION: Chief cell secrete pepsinogen Parietal  cell secrete   hydrochloric  acid and intrinsic factor Gastric acid secretion regulated by  Acetylcholine   - muscarinic  receptor Gastrin - g receptor Histamine- h2 receptor Acetylcholine and gastrin act on parietal  cell Act indirectly on enterochromaffin cells releasing  histamine Mucosa secretes mucus  which forms the protective layer ,bicarbonate and prostaglandin Prostaglandin  stimulate mucus and bicarbonate that leads to vasodilation  and thereby inhibit gastric  secretion  CLASSIFICATION : DRUG FOR PEPTIC ULCER : A) GASTRIC ACID SECRETION INHIBITOR : H2 antihistamine - CIMETIDINE,RANITIDINE Proton pump inhibitor - OMEPRAZOLE,LANSOPRAZOLE B) GASTRIC ACID NEUTRALIZER : Systemic - sodium bicarbonate,sodium citrate Non systemic - magnesium hydroxide,calc