Pharmacology Flashcards
What are 2 classifications of bacteria?
- Aerobic- bacteria need o2 to survive!
- Tuberculosis and pseudomonas
- Anaerobic - bacteria that do not need 02, they rely on fermentation.
- Tetanus is an example of this- found in soil, ash, and animal faeces.
- Bacteriodes fragilis which lives in the gut
Gram + and Gram -
- Gram + have a thick peptidoglycan layer
- Gram - have a thin peptidoglycan layer
- Contains an additional outer membrane outside the peptidoglycan layer which contains lipopolysaccharides
Antibiotic classes
Blue- bacteriostatic- stops the bacteria growing without killing it, allowing our immune system to come in and attack!!
Red- bactericidal- kills bacteria, it destroys it!
Beta Lactams
- Penicillin, amoxicillin
Major antibiotic that exist - With the cell wall down, the antibiotic can kill the bacteria as it is a bactericidial bacteria.
Glycopeptides
- Cell wall synthesis inhibitor
- They nuzzle into the cell wall itself and pick away at the enzymes, preventing them from coming in.
- Glycopeptides are a last resort!- because of their inefficiency in treating
- They inhibit RNA synthesis
Ribosomes
- Protein producing factories, essential for all living things
- There are 2 subunits that come together to make the proteins
- Small subunit is responsible for reading genetic code- 40S
- Large subunit-50S helps link the amino acid together to build the protein chain.
Protein synthesis
- DNA is sent out via RNA (messenger). MRNA is a blueprint that travels out of the nucleus into the cytoplasm into the ribosomes.
- MRNA is the genetic code
- The TRNA (transfer) carries the amino acid to the proteins
Protein synthesis inhibitors
- Tetracyclines- Treat acne, binds to 30S and prevents MRNA coming in.
- Aminoglycosides
- Macrolides- protein static, allow immune system to come in
-Oxazolidinones- used to treat TB, binds to 50S, Prevents TRNA coming in
-
Streptogramins
- Strong antibiotic
- 2 components: A&B, inhances antibacterial effect as they work together.
- A blocks enzyme that produces the bonds, base of protein falls apart without this
- B binds to different site of ribosome which prevents the release of that protein chain
- When VRSA does not work
DNA SYNTHESIS
- Double helix unwinds forming 2
- It unwinds because of helicades
Mycolic acid synthesis inhibitor
Folic acid synthesis inhibitor
- We gain folate from our diet as the body can’t make it
- Bacteria can’t get folate so has to make its own
- PABA converts into DHF
SIDE EFFECTS OF ANTIBIOTICS
- Antibiotics can also target beneficial bacteria, doing so prevents them from working leading to DIARRHOEA!
- Allergic reaction- Abx TRIGGER AN IMMUNE RESPONSE
- Metabollic effects, by altering how the liver processes medications
- May alter CNS causing seizures§, confusion and hallucination
Prescribing Issues
Elderly:
- Treat the disease rather than the symptoms
- Be cautious about adding new meds
- Start low, go SLOW!- due to pharmacokinetics, the elderly struggle to metabolise drugs, with smaller doses, they can metabolise quicker:)
- Monitor adverse reactions- may lead to falls, confusion, incontinence, depression
Prescribing issues
PAEDS:
- Abx is last resort in paeds as you don’t want them to become intolerant/resistant!
- Per KG bases as average dose could be toxic for paeds
