Drugs! Flashcards
When performing an X-ray with iodine containing contrast, such as intravenous urography, which drug is a contraindication?
Metformin
What is Metformin?
An antidiabetic drug and is first choice in overweight patients where strict dieting has failed.
Which two antibiotics should be used for a septic urinary stone?
1g IV ampicillin and IV gentamicin.
What class is ampicillin and what is it’s mode of action?
Beta-lactam. It is able to penetrate both gram-negative and gram-positive bacteria. It inhibits the action of transpeptidase, which bacteria need to make their cell wall, this causes cell lysis.
What class is gentamicin and what is its mechanism of action?
Aminoglycoside. It is a bactericidal antibiotic, it binds to the 30s subunit of the bacterial ribosome interupting protein synthesis.
Which two drugs does Jay Khastigir say are used in medical expulsion therapy for kidney stones?
Alpha blockers and Nifedipine.
Which drug is a synthetic replacement for vasopressin? And what does it do?
Desmopressin, encourages water retention by reducing urine output, useful for obstructed ureters.
What is Heparin and what is its use?
It is a glycosaminoglycan, and is used as an anti-coagulant. It binds to antithrombin III which activates AT and allows it to deactivate thrombin and other proteases involved in clotting.
What is Atropine?
It is a muscarinic antagonist, used to dilate the pupils.
What is Doxazosin and what is its function?
It is an Alpha-1 antagonist used to treat hypertension.
What is Salbutamol and what is its function?
It is a Beta-2 agonist used in the treatment of asthma.
What is Timolol and what is its use?
It is a non specific Beta antagonist and is used in the treatment of glaucoma.
What is Bisoprolol and what is its use?
Bisoprolol is a Beta-1 antagonist and is used used to treat hypertension and cardiac ischaemia.
What drug is used to dilate the pupil and what is its mechanism of action?
Atropine, muscarinic antagonist so decreases the input of the parasympathetic system.
What drug is an Alpha-1 antagonist that is used in the treatment of hypertension?
Doxazosin
Which drug is a Beta-2 agonist used in the treatment of asthma?
Salbutamol.
Which non-specific Beta-antagonist is used in the treatment of glaucoma?
Timolol
Which Beta-1 antagonist is used in the treatment of hypertension and cardiac ischaemia?
Bisoprolol
What is orlistat?
Orlistat is a weight loss drug, it inhibits the production of lipase, so fats are less absorbed.
What is the name of the weight-management drug that can cause malabsorption and steatarrhoea?
Orlistat.
What is syntocinon used for?
Synthetic Oxytocin - Used to create more regular and efficient contractions during labour.
Why does oxytocin need to be given I.V.?
It is destroyed in the gastrointestinal tract.
What is ergometrine?
It is used in obstetrics to facilitate the delivery of the placenta and to reduce bleeding, as such it is used to reduce post-partum haemorrhage.
What is Prostin?
It is the trade name for Prostaglandin E2, and is used to help soften the cervix.
What is syntometrine and what is its use?
- Oxytocin and Ergometrine
- Used in the active management of the third stage of labour, to help deliver the placenta and prevent post-partum haemorrhage.
What class is Benzylpenicillin, what are it’s uses and mechanism of action?
- Known as penicillin G and is the gold standard penicillin.
- It is given parenterally.
- It is a penicillin antibiotic.
- Bacteriacidal, it disrupts the wall of the bacteria eventually causes lysis.
What class of antibiotics is Clarithromycin, what are it’s uses and mechanism of action?
- It is a macrolide.
- It binds to 50s subunit of the bacterial ribosome and thus prevents them from producing proteins.
- It is predominantly used to treat respiratory tract infections and skin infections.
What class of antibiotics is Cefuroxime, what are it’s uses and mechanism of action?
- Cephalosporin
- It is less susceptible to Beta-lactamase and so is used in the treatment of haemopholus influenza, gonorrhoea and Lyme disease.
- Work in a similar manner to other Beta-lactams by disrupting the cell wall by disrupting peptioglycan synthesis.
What is Coamoxiclav?
- It is a combination of amoxicillin (a beta-lactam) and clavulanic acid (a beta-lactamase inhibitor).
- This gives it a broader spectrum and has more resistance to beta-lactamase producing bacteria.
- Used broadly for UTIs, RTIs and skin infections.
What class of antibiotics is amoxicillin, what are it’s uses and mechanism of action?
- It is a beta-lactam antibiotic in the aminopenicillin family.
- It is better absorbed after oral consumption than other beta-lactams.
- As with other beta-lactams it disrupts the bacterial cell wall and causing lysis.
What class of antibiotics is metronidazole, what are it’s uses and mechanism of action?
- It is a nitroimidazole antibiotic.
- It is used predominantly for anaerobic bacteria and protozoa.
- It is absorbed by the bacteria where it is then reduced and forms bonds with enzymes within the bacteria thus making them unavailable for use.
Which class of antibiotics is Rifampicin, what are it’s uses and mechanism of action?
- It is a rifamycin antibiotic.
- It is used in the treatment of TB, Mycobacterium infections, MRSA (methicillin-resistant Staphlycoccus aureus) amongst others.
- It works by inhibiting RNA synthesis by binding to RNA polymerase.
Which class of antibiotics is Flucloxacillin, what are it’s uses and mechanism of action?
- It is a beta-lactam of the penicillin class.
- It has a narrow-spectrum but it beta-lactamase stable so can be used to treat beta-lactamase producing organisms.
- As with other beta-lactams it disrupts the bacterial cell wall resulting in lysis.
Mycobacterium, Legionella, Listeria and Chlamydia are all bacteria that become intracellular. Which four classes of antibiotics can pass into mammalian cells?
- Glycopeptides.
- Macrolides.
- Quinolones.
- Tetracyclines.
What is Loperamide? What is its mechanism, indications and side-effects?
- It is an antimotility drug.
- Used in the symptomatic treatment of acute diarrhoea.
- It is an opioid receptor agonist, which decreases the activity of the myenteric plexus, leading to decreased tone of the longitudinal and smooth muscle of the intestinal wall.
- Abdominal cramps, dizziness.
Ipratropium: What is it? What’s its mechanism, indications and side-effects?
- Antimuscarinic bronchodilator.
- Muscarinic receptor antagonist, causing the bronchi to dilate.
- Indicated for reversible airway obstruction, particularly COPD.
- Side-effects are minimal but dry-mouth is common.
Lorazepam: What is it? What’s its mechanism, indications?
- Benzodiazepine.
- Used as short-term treatment of anxiety disorders.
- It has all six intrinsic benzodiazepine effects.
What are the six intrinisic benzodiazepine effects?
1) Anxiolysis.
2) Anterograde amnesia.
3) Sedation.
4) Anti-emesis/nausea.
5) Muscle-relaxant.
6) Anti-seizure.
Tramadol: What is it? What’s its mechanism, indications and side-effects?
- Opioid analgesic used for moderate to severe pain.
- It produces by two mechanisms: Opioid effect and an enhancement of serotonergic and adrenergic pathways.
- It has fewer of the typical opioid side-effects, but; nausea, vomiting, constipation, dry mouth, diarrhoea, retching, fatigue, paraesthesia.
How does the opioid system work?
Opioids are a psychoactive drugs that resemble morphine, they bind to opioid receptors found in the digestive tract and CNS. Binding to these receptors causes their beneficial and adverse effects.
Ondansetron: What is it? What’s its mechanism, indications and side-effects?
- It is a serotonin 5-HT3 receptor antagonist used for the treatment of nausea and vomiting caused by cancer chemotherapy, radiotherapy and surgery.
- Serotonin is released by enterochromaffin cells in the small intestine in response to chemotherapy, and initiate vomiting.
- Constipation, headache, flushing and injection-site reactions.
Metyrapone: What is it? What’s its mechanism, indications and side-effects?
- It is a competitive inhibitor of 11ß-hydroxylation in the adrenal cortex, the resulting inhibition of cortisol leads to an increase in ACTH hormone which leads to the increased release of cortisol precursors.
- It is therefore used as a test of anterior pituitary function and has also been used in controlling the symptoms of Cushing’s syndrome.
- It can cause nausea, vomiting, dizziness, headache, hypotension, sedation.
Spironolactone: What is it? What’s its mechanism, indications and side-effects?
- It is a potassium sparing-diuretic that acts by antagonising aldosterone.
- It is used in the treatment of ascites and oedema in cirrhosis of the liver, malignant ascites, nephrotic syndrome, oedema in congestive heart failure and moderate to severe heart failure.
- It is also used in the treatment of primary hyperaldosteronism (Conn’s syndrome).
- Side-effects include GI disturbances, hepato-toxicity, malaise, confusion, drowziness, gynaecomastia.
Simeticone: What is it? What’s its mechanism, indications and side-effects?
• It is an anti-foaming agent that is added to antacids to relieve flatulence.
Sucralfate: What is it? What’s its mechanism, indications and side-effects?
- It is a complex of aluminium hydroxide and sulphated sucrose that protects the gut mucosa from acid and pepsin attack.
- Used for gastric and duodenal ulcers.
- It can cause diarrhoea, constipation, nausea, indigestion, flatulence, gastric discomfort, back pain, dizziness, headache, drowsiness.
Misoprostol: What is it? What’s its mechanism, indications and side-effects?
- It is a synthetic prostaglandin analogue, that promotes the healing of peptic ulcers. It can prevent NSAID-associated ulcers and so is used in the elderly for whom NSAIDS cannot be withdrawn.
- Side-effects - Diarrhoea, abdo. pain, dyspepsia, flatulence, nausea and vomiting.
Domperidone: What is it? What’s its mechanism, indications and side-effects?
- It is a motility stimulant, a dopamine receptor antagonist which stimulate gastric emptying and small intestinal transit, and enhance the strength of the LOS.
- It is indicated for nausea and vomiting, GORD and dyspepsia.
Metclopramide: What is it? What’s its mechanism, indications and side-effects?
- It is a dopamine receptor agonist which stimulates gastric emptying and small intestine transit, and enhance the strength of the LES.
- It is indicated in adults for nausea and vomiting, GORD and treatment with cytotoxics or radiotherapy.
Ranitidine: What is it? What’s its mechanism, indications and side-effects?
- It is a H2-receptor antagonists, which heals gastric and duodenal ulcers by reducing acid output.
- It indicated in the treatment of PUD and GORD.
- Side-effects include diarrhoea, headache and dizziness.
Omeprazole: What is it? What’s its mechanism, indications and side-effects?
- Omeprazole is a PPI which inhibit gastric acid secretion by blocking the proton pump of the gastric parietal cell.
- It is indicated for PUD, GORD, Zollinger-Ellison syndrome.
- Side-effects include GI disturbances and headaches.
