pharmacology 3 Flashcards
please remember to check on how metabolism is affected by certain drugs
what is meant by systems framework
this is a framework that is used to give a system structure , the processes and the outcomes
factors that are involved in the work system
technology and tools
organisation
tasks
environment
what is meant by a systems approach to ADME
this means that there is a system that helps with the process of ADME and there are some likely consequences.
what does system comprise of
people
tools
tasks
organisation
environment
how does systems affect the absorption of a drug
1.people-that is factors that affect the individual person that is cognitive state of mind , other physiological factors ,inflammation , the fear that is within a person.
2.tools-that is the tools that are required to facilitate the absorption of the drugs that means presence of storage material etc.
3.tasks- refers to the tasks to be done before the administration of the drug that is shaking.
4.organisation - the money to buy the fridge , availability of support etc.
5. environment - temperature , design of material etc.
how does system affect the distribution of a drug
the systems that is people may have an adverse effect towards the insulin that is produced synthetically and they may not have a reaction towards natural animal insulin however the medical profession people refused their right to an informed choice of insulin treatment.
what is hypoglycaemia unawareness
this refers to the state of being unaware of the symptoms of a certain disease
how does the system affect distribution in the case of insulin
polymorphism ;this will affect the receptors of the drug , the drug solubility sometimes insulin may be more lipophilic in other people than in others , there could also be increased protein binding.
how does system affect metabolism of drugs
1.genetic variation of the CYP2C9 enzyme may lead to poor metabolism of the drug warfarin, example is people with 2 and 3 polymorphism will be poor metabolisers of the drug.
2.warfarin build up is a narrow therapeutic index.
how is excretion influenced by systems
Metformin: ‘biguanide’ – first-line drug treatment in T2DM
* Monotherapy or with other drugs (including thiazolidinediones)
* Effects are complex: reduces hepatic glucose production (inhibits
gluconeogenesis)
* Increases FAO in muscle; enhances insulin sensitivity
* Inhibits mitochondrial respiration in liver – lactic acidosis
* Not metabolised
* Excreted unchanged in urine (renal clearance much higher than GFR)
systems approach to renal excretion
1.Transporters involved in secretion that is OCT -2 ,MATE-1
2.polymorphic variants of the transporters .
3.Drugs like sulphonylureas and TZDs inhibit OCT activity.
4.H2RA cimetidine
5.kidney function dehydration.
6.other factors such as drinking factors for people with incontinence such as old people, often stress that tends to affect women more ,
7.persons with restricted mobility such as self catheterisation , restriction of fluids in the plane where there are no toilets .
how is methotrexate (MTX) affected by system.
1.15mg methotrexate (MTX), once weekly
(to be dispensed as 2.5mg tablets) example is folic acid.
2.Risks arise from systems issues like tablet strength confusion (2.5mg vs. 10mg).
Patient safety depends on understanding perspectives and workflows.
a systems approach to insulin
1.Absorption: Factors such as inflammation, injection technique, and temperature impact effectiveness.
2.Distribution: Variation in human vs. animal insulin; challenges like hypoglycemia unawareness.
3.Complexity in patient behavior (e.g., fear, depression) and tools (e.g., vials, monitoring).
a systems approach to warfarin
1.Metabolism affected by CYP2C9 polymorphisms and ethnic variations (e.g., *2, *3 alleles).
2.Narrow therapeutic index increases risks, demanding precise dosing and monitoring.
a systems approach to metformin
1.Excreted unchanged in the kidneys via OCT-2 and MATE-1 transporters.
2.Renal function, fluid intake, and physical barriers (e.g., accessing toilets) affect clearance.
what is drug to drug interactions
this is the modification of a drug`s effect by prior or concomitant administration of another drug ,herb ,foodstuff and drink
object drug
a drug whose activity is altered
precipitant drug
the agent that precipitates an interaction between a drug
reasons for drug to drug interactions
1.increasing action of drug for example co amoxiclav which is amoxicillin plus clavulanic acid.
2.antibiotic resistance -beta lactamase
3.efflux pumps - they prevent drugs from accumulating in the cells.
4.multidrug resistance
what are the factors that may cause drug interactions in patients
1.multiple prescribers
2.self prescriptioning that is the use of over the counter medication and the use of food supplements etc .
3.length of the hospital stay .
4.age
5.polymorphisms that is the different genetics contribute to the interactions between the drugs.
6.change in the blood levels for potent drugs will have a harmful effect.
drug interactions how do they affect absorption of the drug
they affect the rate at which the drug is absorbed.
what problem is formed when there is a complex formation that causes inhibition of absorption
there is a short half life that means a large amount of the drug is needed to achieve therapeutic levels rapidly .
chelation
process where drugs bind to the metals in the blood to form complexes that cannot be absorbed by the cells.
example of a drug that undergoes chelation
tetracycline and calcium
