Drugs Flashcards
What is the mechanism of bronchodilators?
Relax bronchial smooth muscle
B2 agonist
Salbutamol is an example
How do anti-muscarinic agents work in resp drugs?
Relaxes bronchial smooth muscle
Ipratropium is an example
What are the SE of Theophylline/Aminophylline?
N&V&D
Palpitations
Narrow therapeutic index
Irritability limit usefulness
How do corticosteroids work?
Reduce inflammation by action on intracellular protein synthesis
Cross membrane
Bind to glucocorticoid receptor
Carried into nucleus
Promote formation of anti-inflammatory proteins
Is IV steroids quicker than PO?
No
Protein formation in the nucleus is a rate limiting factor
Therefore PO acts just as fast as IV
Which antihistamines are sedating & non-sedating?
Sedating: Chlorphenamine
Non: Cetirizine
What type of hypersensitivity does antihistamines work against?
Type 1 hypersensitivity
What benzos have a long, intermediate & short half life?
Long: Diazepam
Intermediate: Chlordiazepoxide
Short: Midazolam, Lorazepam
What usually triggers lithium toxicity? Why?
Dehydration
Diuretic use
Lithium & Na in same chemical group
Body tries to conserve Na but at the same time conserves Li causing build up
What are the Sx of Li toxicity?
Non-specific
Confusion
Tremor
Ataxia
Poor concentration
GI Sx
What is the mechanism of SSRIs?
Act on presynaptic serotonin reuptake
What are the effects of overdose of Tricyclics?
Anticholinergic effects (urine retention, dry mouth, hot)
Cardiac conduction abnormalities (tachyarrhythmias, HB, prolonged QRS)
Respiratory depression
Convulsions
Metabolic acidosis
What are the Sx of Serotonin syndrome?
High temp/sweating
Tachy
Confusion/agitation
Muscle twitching
Diarrhoea
What drug groups can cause serotonin syndrome?
MAOIs
SSRIs
What are the SE of antipsychotics?
Anticholinergic effects
Extrapyramidal effects
Photosensitivity
Neuroleptic malignant syndrome
Give an example of a Butyrophenone
Haloperidol
What are the atypical antipsychotic drugs?
Olanazpine
Quetiapine
Clozapine
Risperidone
Aripiprazole
What are the indications for Carbemazepine?
Focal seizures
Grand Mal seizures
What is the indication for Valproate?
Grand Mal seizures usually in children
How does Penicillin work?
Cell wall disruption
Pen V: Works on S. Viridans, S. Progenies
What does Amoxicillin work against?
Many Gram +ve
Respiratory organisms
Some Gram -ve organisms
Some resistance in S. Pneumonia & H. influenza
How does Co-Amoxiclav work?
Beta lactase inhibited by Clavulanic acid
Allows penicillin to act on cell wall
Cover s both Gram +ve & -ve
When are 3rd generation cephalosporins used?
Meningitis
Gonorrhoea
How do sulphonamides work? What do they work on?
Act on folate pathway, similar to Trimethoprim
Can be used to Strep, Staph, E.Coli, H.influ
What are examples of Macrolides? What is it used against?
Erythromycin
Clarithyromycin
Mycoplasma, atypical pneumonia, campylobacter, pertussis
How do macrolides & Clindamycin & Tetracyclines work?
Bind to ribosomes and inhibit protein synthesis
How is Clindamycin good for osteomyelitis?
90% Oral bioavailability
Good tissue penetration
Good for anaerobic treatment
What are tetracyclines used against?
Malaria
Rickettsia
Lyme disease
Chlamydia
Doxy: Resp diseases
Why do we avoid giving tetracyclines to children?
Cause issues with teeth and bones
Teratogenic
What do ahminoglycosides work against?
Gram -ve
Majority susceptible but some resistance via plasmids
Why is Nitrofurantoin not used in pyelonephritis?
Poor tissue absorption
25% drug conc found in urine
What does metronidazole work against?
Anaerobes
Protozoa
C. Diff
H. Pylori
What drug group can cause tendon rupture?
Quinolones
How does Chloramphenicol & Fusidic acid work?
Disruption of protein synthesis
Why’s Chloramphenicol no longer given as a tablet?
Can cause fatal aplastic anaemia
What anaesthetic agents inhibit NMDA receptors?
Ketamine
NO
Xenon
