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Flashcards in Drug Delivery Deck (20)
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What are the 4 main reasons to change the route of administration for a pain medication?

If different drug profiles are needed (eg, quick acting or prolonged acting)


To avoid the 1st pass effect


To have efficient, non-invasive delivery


Patient factors (eg, age/dexterity/support)


What is an Abuse-Deterent Formulation (ADFs) of opioids?

A formulation in which the opioid is rendered useless if the tablet/capsule has been tampered with




How much more potent than morphine is fentanyl?



Name 4 ways that a Abuse-Deterent Formulation can be made

Physcial Barrier (gel) --> Solids that become viscous when alcohol is added to extract the drug


Aversion --> Utilizes a noxious powder in the formulation to act as a deterrent


Agonist/Antagonist --> Naltrexone is added to morphine, which if chewed will be released, reducing the euphoria that is gained from the morphine


Pro-Drug --> The active drug is only avaliable once consumed


What type of fentanyl patch is Duragesic?


And what type are the newer generics?

Duragesic --> Reserviour System


Generics --> Simple adhesive-type


How can patches be abused?

Removal of the gel and boiling --> Allows the opioid to be injected or drunk


Chewing of the patch --> Released all 3 days worth via the mucosa


What is the benefit of Fentanyl Citrate?

The most lipophillic IR opioid --> so has a rapid onset of action as can pass through membranes rapidly


Can be used submucoasally as Oral Transmucosal Fentanyl Citrate (OTFC) for BTcP



What is a Copy-Number Variation (CNV)?

Either a gene deletion (loss of function) or gene duplication (increase expression and hyperactivity)


Explain the following..




Germline Genetic Variation


Somatic Genetic Variation

Halpotype --> A group of allelles across several genes on the same chromosome that are close together and so tend to be inherited together 


Germline --> Variation of DNA that is present at conception, and so is passed down to offspiring


Somatic --> Changes in DNA that occur spontaneously after conception, and so aren't passed down to offspring


What's the difference between pharmacogenetics and pharmacogenomics?

Pharmacogenetics --> Study of the variability in drug response due to hereditary factors, with focus on a single gene or several genes


Pharmacogenomics --> Whole-genome application of pharmacogenetics

- Genome-wide analysis of the genetic determinants of drug efficacy and toxicity


Define Actionable Genetics

Where we could change therapy due to the genetic variability of patients (18% of US prescriptions)


What are the effects on being either a Poor Metaboliser (PM) or a Ultra Metaboliser (UM)?

PM --> ADRs at normal doses

- No/poor response to drugs that require activation (eg, pro-drugs)


UM --> No/poor repsonse to usual doses (eg, antidepressents)

- Toxicity after pro-drugs (eg, codeine)


What's the difference between a Genotype and a Phenotype?

Genotype --> An individuals full hereditary information ("Born with it")

- Eg, A pair of alleles regarding the CYP2D6 genotype


Phenotype --> The individuals actually expressed properties/oberservable characteristcs (eg, metabolism of tamoxifen)


Why do Poor Metabolisers (PM) get less of a benefit from tamoxifen?


Which class of drugs would be better for them?

As tamoxifen is broken down to more active metabolites....which is a slower process in PMs


They would get better outcomes by taking aromatase inhibitors


Why is genetic testing useful before giving treatment with 6-MP?

As if people have inactive forms of TPMT they cannot break down 6-MP, so the cancer therapy is toxic


Slow metabolisers will therefore need to have lower doses and shorter durations of treatment


What are the 3 criteria needed for a Pharmacogenomic (PGX) test to be done in hospitals?

Analytical Validity --> Ability of a test to measure accuratly and reliably the genotype of interest


Clinical Validity --> The accuracy with which the test can detect the prescence of the target phenotype/disease


Clinical Utility --> Whether use of the test will improve health outcomes, due to the potential risks of the test itself (often money based)


What are the 3 ways that the FDA and EMA support the integration of PGX tests?

Include PGX data in drug labelling


Use PGX data to choose dose regime and identify patients at risk


Use of a PGX label when PGX data is of high importance for treatment outcomes


When can the Cockroft and Gault equation not be used?

When the patient is not in steady state (eg, renal function must be fairly stable)


Extreme muscle mass


Obesity or ascites


When should TBW be used instead of IBW?

In obese patients to ensure they're not under-dosed!


What is the Calvert Equation?