Variations in Drug Action and Effect Flashcards
What terms are preferred to be used when talking about the extent to whcih a person takes his/her medication?
Adherence or concordence now preferred terms to compliance as they emphasise a partnership between the person adn the HCP in the process of taking medicaitons, rather than simply following instructions.
List 10 reasons for poor drug adherence
- poor knowledge of the illness and medication.
- administering and dosage of the medication.
- independent pausing, stopping or controlling of the medication.
- lack of competence in self-managment
- hiding the drug information (e.g. drugs prescribed by private doctors)
- fear towards drugs
- media and neighbours as source of medication information
- diseases where poor control of medication does not immediately present with symptoms
- challenges with lifestyle changes
- replacing prescription drugs with self-administered drugs
List some (5) patient oreinted approaches to improving adherence
- Focus on health outcomes of self-management and drug therapies
- support for patients to better understand their disease and its management
- pharmacists as coaches for drug therapies
medication counselling for caregivers
peer groups for chronic conditions and training in peer groups.
List some doctor/prescriber orientated approaches to improving adherence
- continuity of care and permanent doctor-patient relationships
- Equal relationships with pts, with a coaching attitude
- setting achieveable goals
List some medication oriented approaches to improve adherence (6).
- Medication reconciliation (nurse or pharmacist)
- medicine optimisation (pharmacist)
- medication review (pharmacist)
- Combination of products to minimise the number of medicines
- Checking and teaching the right use of medical devices
- use of calender packs or prepacked dispensing boxes
Name 7 things to tell patients or that patients may want to know about the drugs they are taking
- the name of the medicine
- the purpose of treatment
- when, how and for how long to take their medicine
- what to do if dose is missed
- unwanted effects and what to do about these
- any necessary precautions to take, such as effects on driving
- any problems with alcohol or other drugs
What can be used as a measure of health literacy in English speaking populations?
the REALM-R list
How does the REALM-R list work? What score suggests poor health literacy?
Ask patient to read the specified list of words. Score for each word pronounced correctly (except first 3, 3-lettered words which don’t get a score and are there to reduce test anxiety).
A score of <7 suggests poor health literacy
How does codeine work as an analgesic?
codeine is a prodrug and is metabolised to morphine, the active opiate, by CYP2D6
What could you do if a patient suffers with drug toxicity from a dose that is considered normal for that person’s age and weight?
Genotype the gene that codes for the CYP enzyme that breaks down the drug.
the patient may be an ultrarapid metaboliser.
What are the implications of being a CYP2D6 ultra-rapid metaboliser and taking codeine?
They will be able to metabolise codeine into morphine quicker so the patient will have higher than expected morphine levels (an initial “overdose”), with more side effects and a shorter than expected duration of pain control
If someone has a genotype result of CYP2D6 diplotype (2A/10)3N, what does the 3N mean?
the 3N indicates there are 3 alleles present so there will be an additional copy of either *2A or *10
How many phenotypes of CYP2D6 are there?
4
What are teh 4 phenotypes of CYP2D6?
ultra-rapid metaboliser (very high activity) Extensive metaboliser (normal activity) intermediate metaboliser (lower activity) poor metaboliser (low or no activity)
What is the most common CYP2D6 phenotype?
Extensive metaboliser - normal activity
other than codeine, which other opiates are affected by the CYP2D6 genetic polymorphism?
hydrocodone
oxycodone
tramadol
Mutations of the gene encoding an enzyme that metabolises thiopurine drugs, such as azathioprine, have been identified in teh population. What is the name of the enzyme?
Thiopurine methyltransferase (TPMT)
TPMT metabolises thiopurine drugs such as azathioprine, mercaptopurine, tioguanine) so what is the effect if a patient has a mutation in the gene encodeing TPMT that means its activity is reduced?
Increased risk of myelosuppression because drug is in system for longer.
What should you do before starting someone on a thiopurine drug?
consider measuring TPMT activity.
Can you give thiopurine drugs to pts with absent TPMT activity?
No - should be avoided
can you give thiopurine drugs to pts with reduced TPMT activity?
only under specialist supervision.
What is the difference between pharmacogenetics and pharmacogenomics
Although both terms relate to drug resposne based on genetic influences, pharmacogenetics focuses on single drug-gene interactions, while pharmacogenomics encompasses a more genome-wide association approach, incorporating genomics and epigenetics while dealing with the effects of multiple genes on drug response.
What does the Medicines Act, 1968, define a medicinal product to be?
any substance or article intended to be taken by or administered to, a person or animal, which contains a compound or compounds with proven biological effects, plus excipients, and may also contain contaminants
When a licenced medicine is prescribed and administered in accordance with teh SPC, then generally there will be no liability attached to the prescriber if what 3 things are stated:
- correct diagnosis
- correct choice of medicine
- pt warned of potential adverse events
