What type of antibiotic is penicillin?
beta-lactam
How does penicillin work?
- It works by interfering with the formation of the cell wall on the bacteria cell (made of PEPTIDOGLYCAN), leading to the weakening and eventually destruction of the bacteria.
- Targets an enzyme called transpeptidase which is involved in cross-linking the building blocks of the wall
- Wall weakens and becomes unstable
- Result is bacterial death (ruptures)
NOTE: TARGET gram +ve bacteria
Name 3 classes of antibiotics in the beta-lactam group?
- Cephalosporins
- Monobactams
- Carbapenems
What were the first penicillins?
The first penicillins were the naturally occurring benzylpenicillins (pencillin G)
What are the differences between Penicillin V & G?
Penicillin G refers to a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive organisms, while penicillin V refers to a member of the penicillin family exhibiting broad-spectrum antibiotic properties.
G - by IV
V - by mouth
What is calcium channel blocker used for?
Calcium channel blockers specifically target the calcium channels in the cell membrane of heart muscle. By blocking these channels, they prevent calcium ions from entering the cells which are crucial for contractibility. Results = decreased workload of heart
*Vasodilator
* BP control - by relaxing blood vessels
* HR control - can slow the electrical conduction in the heart
* Agina treatment - dilate coronary arteries and increase blood flow
* Ends in “dipine, zem or amil”
What is a beta blocker used for?
They work by blocking beta1 adrenergic receptors on the S.A. and A.V. nodes of the heart & the effects of adrenaline (epinephrine) and other stress hormones on the heart and blood vessels
- Sympathomimetic
- Reduce HR and contractility therefore ↓ CO
- Angina treatment
- HF management
- Ends in “lol”
Explain some advantages and disadvantages of beta blockers
Advantages:
Can treat multiple conditions
reduce risk of cardiac events
Symptom improvement
well established safety profile
Disadvantages:
fatigue/depression
supression of beta 2 receptor - cause bronchoconstriction
cold peripheries
What are protein pump inhibitors (PPIs)?
- Used to reduce the production of stomach acid from parietal cells.
- Treatment for GORD/GERD & peptic ulcers - also helps get rid of H.pylori.
- Short term rather than long term.
What are the side effects of PPIs?
Long-term use or overuse may be associated with certain risks and side effects, including an increased risk of bone fractures, vitamin and mineral deficiencies (such as vitamin B12, magnesium, and calcium), gastrointestinal infections, and rebound acid hypersecretion
List the main asthma medications and characteristics
- Sympathomimetics - eg. Salbutamol
* Activate receptors in the SNS (stimulates)
* Agonists at the beta2 adrenergic receptors on the bronchiole smooth muscles opening them up
* Can also bind to beta1 receptors – causing tachycardia, palpitations, anxiety - Anticholinergic - eg. Atrovent
* Used in moderate/severe cases
* Use them in combi with other drugs above
* To open airways up - Corticosteroids eg. Prednisone
* Reduce swelling and inflammation
* Can take a long time for full effect
* People on longer than 7 days – need to be weaned off
* Intracellular process – bind to nucleus and changes the gene activation, alters proteins and alters inflammatory mediators
Explain the use the oxygen in asthma excaberation
- Airways get narrower, making it hard to breathe. Hypoxia is primary cause of death from this. Use a preventer.
- O2 should be titrated.
- Oxygen supplements should be provided for patients with oxygen saturation levels below 92% in room air, and patients should be weaned from oxygen when the saturation level exceeds 94%
What are the side effects of AB Penicillin?
- Nausea
- Diarrhoea
- Thrush
- Headache
- Allergic reactions: itch/rash, swelling, anaphylaxis - 15% of pop have allergy
- Hairy black tongue
What do betalactamase enzymes (found in some bacteria) do to penicillin?
Act like scissors - cut through beta-lactam ring in penicillin rendering it useless against bacteria.
EXAMPLE = can be found in MRSA
What class of drug is Metoprolol and how does it work?
- Beta-blocker
- Blocks beta-1 receptors located on heart.
- Blocks effects of noradrenaline & adrendaline on heart
- Reduce HR & contraction = Helps reduce CO therfore BP
- Reduce myocardial workload (and afterload)
3 key goals for treating hypertension
- OUTPUT - reduce CO (beta blockers and calcium channel blockers)
- VOLUME - reduce plasma volume (diuretics)
- RESISTANCE - reduce peripheral vascular resistance (vasodilators)
NOTE: BP = CO × TPR illustrates how blood pressure is influenced by both the amount of blood pumped by the heart and the resistance encountered by blood flow in the peripheral vasculature.
What are the 4 x P’s of PPIs?
Prazole
Prevent holes
Porous bones
Possible GI infections
