Respiratory System Flashcards
Pathology of cough
Irritation of lungs- stretch receptors get activated-vagus nerve takes the impulse (sensory) to cough Center in the brain-motor nerve takes it from brain to muscles: diaphragm and respiratory muscles
Drugs for cough (4)
Expectorants
Antitussives
Antihistamines
Demulcents
Moa of action of expectorants and types
Bronchus -> mucus->expel as sputum.
Rx for productive cough. Mc infection.
Mucolytic:
Mucus gets liquified by breaking disulphide bonds
Eg: B: bromhexol
A: Ambroxol
N: N-acetylcysteine
Mucokinetic- increased ciliary movements
Guaiphenesin
What are the antitussives?
Peripherally acting : act on stretch receptors and vagus nerve
Prenoxdiazine
Benzonotate + local anaesthetic
Centrally acting : act on brain
Opioids- morphine, codiene
Dexomethorphan- NMDA antagonist
Noscapine - sigma agonist
Antihistamines for cough and. Demulcents
Antihistamines: act on both central and peripheral
Cetrizine
Promethazine
Diphenhydramine
Demulcents: soothens bronchus and relieves irritation.
Mulethi + honey
What are the bronchodilators for acute asthma ? (5)
B2 agonists: selective: salbutamol
Non selective : adrenaline
Anticholinergics
Methylxanthines : Theophylline
Iv MgSO4
Iv hydrocortisone
Drug given for acute exacerbation of asthma
ICS+ formoterol
Formoterol although is a LABA; has quick onset while longer action.
LABA should not be used alone. Why?
They alone can’t control the underlying I.F and should always be given with ICS.
Drug given for prophylaxis of asthma
Drug given for acute asthma when the patient is taking beta blockers :
LABA > AMA
AMA> LABA ie; iprotropium bromide
MOA of theophylline (3)
- PDE inhibitor
- Adenosine A1 antagonist
- Histone deacetylation
Adverse effects of adenosine A1 receptor
- CNS : Sedation
- Anti diuretics
Therefore theophylline and caffeine ; which are methylxanthines inhibit these actions .
Increased dose of theophylline is required in: (3)
- Smokers
- Children
- CYP 450 inducers :
Rifampicin, Barbiturates, Phenytoin
Theophylline decreased dosage is required in :
- Old age
- Liver failure
- CYP450 inhibitors:
Erythromycin, Clarithromycin
Ciprofloxacin
Allopurinol
Cimetidine
Theophylline is given orally why?
Coz it’s poorly water soluble , hence aminophylline- theophylline + ethylenediamine is water soluble and can be given iv
Theophylline toxicity symptoms. Normal level:
Normal level: 5-15microgm/ml
- Gi symptoms: N/V/ab pain
- Cardiovascular: decreased Bp ->reflex tachycardia -> arrhythmias
- CNS: insomnia —> seizures
Exercise induced asthma. Pathology
DOC
Drug given 20 mins before exercise
Hyperventilation—> increased osmolarity of airways —> mast cell release.
DOC : inhaled CS daily
SABA.
S/e of ICS (2)
Prevented by:
Rx: for s/e
Oral Candida
Hoarseness of voice
Prevented by : gargles, spacer
Rx: nystatin, fluconazole
MOA of ICS (2)
- Inhibit synthesis of all cytokines
- Inhibit NFkB transcription factor that induces production of TNF-a
Egs of mast cell stabilisers (3) MOA
Nedocromil sodium
Cromolyn sodium
Ketotifen
Stabilizes mast cells and recruitment of eosinophils
MOA of monteleukast and zileuton
Monteleukast:
LT receptor inhibitor: blocks production /activity of leukotrienes involved in I.F and bronchospasm.
Zileuton:
5 lipo oxygenase inhibitor.
Decreases leukotriene production.
S/e of monteleukast (2)
It is useful in ……asthma
- Suicidality
- Churg Strauss syndrome
Aspirin induced asthma
PDE inhibitor with respect to respiratory system
Roflumilast -PDE4 inhibitor - used for COPD
Anti-IgE antibody
Anti-IL5 antibody
Anti-IL5R antibody
Anti-TSLP (thymic stromal lipoprotein)
- Omalizumab
- Mepolizumab, Reslizumab
- Benralizumab
- Tezepelumab
Paradoxical bronchoconstriction occurs with ..(2)
- Nebulised SABA : salbutamol, albuterol
- Ipratropium bromide
—with high flow oxygen saturation >92%
MOA of paradoxical bronchoconstriction (4)
- Hypotonic nebuliser solution
- Antibacterial addictives : EDTA
- Prejunctional M2 blockade: ipratropium
- IgE mediated reaction to recipients in metered dose inhaler : soybean,lecithin
MOA of INH
INH resistance is associated with ….(2) activity.
Inhibit mycolic acid synthesis by inhibiting INH -A gene responsible for carrier of FAS2.
Catalase and peroxidase activity
Drugs metabolised by acetylation
CHIPPS
C- clonazepam
H- hydralazine
I- INH
P- propanamide
P- PAS
S- sulfonamide+ dapsone
Most hepatotoxic drug is …..
Least hepatotoxic drug is ….
Other side effects of INH (3)
Pyrazinamide
Ethambutol and streptomycin
- Peripheral neuritis
- Hemolysis in G6PD
3 drug induced SLE
MOA of rifampicin
Blocks RNA synthesis by inhibiting DNA dependent RNA polymerase : gene : rpoB gene
Light chain proteinuria is a side effect of ….
Rifampicin
Mycobacterium drug most effective against :
1. Rapidly growing ( wall of Cavitary lesion)
2. Slow growing
3. Spurters ( caseous material)
- INH
- Pyrazinamide
- Rifampicin
Longest post antibiotic lag period for:
1st line drugs
2nd line drugs
- Streptomycin : 8-10d.
- Maxifloxacin : 15 d
Ethambutol is avoided in children due to …
Vision disturbance (red-green disturbance difficult to detect in children)
Most potent first line ATT
Least potent first line ATT
- Most potent : Rifampicin
- Least potent : Ethambutol
Second line ATT that are bactericidal (2)
- Bedaquiline
Delamanind
ATT used in for HIV coinfected individuals
S/e (3)
Rifabutin
- Uveitis
- Clostridium difficicle diarrhoea
- Pseudojaundice coloured skin
Drug most useful in MDR tb
It comes under ……gp. It is bacterio….
Ethionamide- INH group of drug, but is bacteriostatic
A polypeptide antibiotic used in TB
MOA
Capreomycin
Inhibit cell wall permiability
MOA of cycloserine
Structural analogue of D Alanine
Inhibit cell wall synthesis
S/e of cycloserine
Drug used to prevent it.
CNS toxicity
Suicidal seizures, peripheral neuropathy
100mg/ day pyridoxine is used to prevent it
Tuberculostatic drug. S/e
PAS
s/e goiter
S/e of thiacetazone (4)
Avoid in……patients. Why?
Agranulocytosis
SJS syndrome
Hepatitis
Ototoxicity
Avoid in HIV patients due to high skin/GI toxicity
ATT used for mycobacterium avium
Clarithromycin
Azithromycin
Linezolid MOA
Gp of ……
S/e (2)
Inhibit 70S ribosomal complex
Gp of oxazolidinones
- Bone marrow suppression
- Peripheral neuropathy
Use of bedaquiline and delamanind
MOA
MDRTb only
MOA:
Bedaquiline: blocks ATP synthase of mycobacteria
Delamanind: inhibit mycolic acid synthesis
S/e of bedaquiline, Delamanind (3)
- Increase AST/ALT
- Serum amylase,lipase
- Qt prolongation
