SOLUTIONS
What is used to calculate a patient's overdose risk? (An actual calculation won't be done
on the exam) - ✔✔ Which schedule drugs can APRNs prescribe? - ✔✔DEA license will
allow for prescribing of Schedules 2-5. There can be restrictions as noted in collaborative
agreement. May be facility/state dependent. Who determines and regulates prescriptive
authority? - ✔✔Determines: Also known as independent prescribing. APRNS can prescribe
without limitation and is state dependent. Includes "legend" (prescription) and controlled
drugs, health/medical services, DME, etc. Regulates: State board of nursing, regulated by
health professional board. Federal government controls drug regulations but has no
control over prescriptive authority. How does limited prescriptive authority impact patients
within the healthcare system? - ✔✔Limited prescriptive authority creates numerous
barriers to quality, affordable, and accessible patient care. For example, restrictions on
the distance of the APRN or PA from the physician providing supervision or collaboration
may prevent outreach to area of greatest need. An increase in patient waits. What are the
key responsibilities of prescribing? - ✔✔The ability to prescribe medications is both a
privilege and a burden. Have a documented provider-patient relationship, do not prescribe
medications to family or friends or yourself, Document a thorough history and physical
examination, include any discussions you have with the patient about risk factors, side
effects, or therapy options, have documented plan regarding drug monitoring or titration, if
you consult additional providers not that you did so. Use the references provided in the
following boxes to assist in safely and rationally choosing one medication over another. Be
sensible, accept responsibility, do not fear it, know constraints and limitations, always
learn and update, keep Rx pads in safe place, confirm allergies, verify medication list with
patient, do not let insurance dictate quantity of Rx, Charting is key (particularly with off
label use), Provide use and rationale. What should be used to make prescribing decisions?
- ✔✔The best way to keep your patients (and yourself) safe is to be prudent and deliberate
in your decision-making process. Cost, availability, current practice guidelines,
medication interactions including interactions with food, side effects, need for monitoring,
how drug is metabolized (hepatic or renal), special populations (pregnancy, nursing, older
adults) Be familiar with pharmacokinetic and pharmacodynamic changes of older adults
and how that would translate to baseline information needed to prescribe -
✔✔Pharmacokinetic is the study of drug absorption, distribution, metabolism, and
excretion in the body. The ability of older adults to metabolize drugs is commonly
decreased. Drug dosages may need to be reduced to prevent drug toxicity. Beer's criteria -
✔✔Guidelines for prescribing medications to patients 65 & older. Drugs on the list should
, be avoided in patients over 65 expect when the benefits significantly outweigh the risks.
The Beers Criteria includes five lists that describe certain medications and situations and
include: potentially inappropriate medication (PIM) us in older adults, PIM use in older
adults due to medication-disease or medication-syndrome interactions that may
exacerbate the disease or syndrome, medications to be used cautiously in older adults,
clinically significant drug interactions that should be avoided in older adults, medications
to be avoided or dosage decreased in the presence of impaired kidney function in older
adults. Why is Beer's criteria important? - ✔✔It provides a list of medications that are
potentially harmful in elderly. List that identifies drugs with a high likelihood of causing
adverse effects in older adults. Beers Criteria are recommendations; ultimately
prescribers must determine whether a medication is appropriate for use or not. These
guidelines are not intended to limit the use of medications or apply to all older adults. Safe
and judicious prescribing is crucial in the older adult to optimize pharmacotherapy.
Impacts/outcomes of polypharmacy - ✔✔Polypharmacy greatly increases the risk for
interactions. Drug interactions with mild side effects to life-threatening consequences.
Elderly is at a higher risk of polypharmacy due to taking five or more medications daily.
CYP450 - ✔✔metabolic pathway, involved in metabolism of drugs in the liver. Metabolism
can be inhibited or induced by drugs and once this happens drug-drug interaction can
occur. What are the CYP450 inhibitors? - ✔✔Liver enzymes. It's not just a single molecular
entity but rather a group of 12 closely related enzyme families. Examples: Valproate,
Isoniazid, Sulfonamides, Amiodarone, Chloramphenicol, Ketoconazole, Grapefruit juice,
Quinidine What do they do? Slows down metabolism of medications. Inhibitors are
medications that inhibit activity of one or more of the CYP450 enzymes. Medications that
inhibit an enzyme can potentially slow that enzymes activity required for metabolism of
other medications, thereby increasing the levels of medications dependent on that
particular enzyme for biotransformation. This inhibition prolongs the pharmacalogical
effects, which may result in toxicity. Factors that affect the inhibition include the dose and
the capacity to bind to the enzyme What do they cause if not used correctly
(CYP450)?(aka:What would the patient experience?) - ✔✔Toxicity. drug build up Examples
of CYP450 inducers? - ✔✔barbiturates, St Johns wart, carbamazepine, rifampin, alcohol,
phenytoin, griseofulvin, phenobarbital, sulfonylureas What do CYP450 inducers do? -
✔✔Increase medication metabolism. Inducers are xenobiotics that elevate the CYP450
enzyme activity by increasing the enzyme synthesis. This action leads to additional sites
available for biotransformation. The increased number of sites enhances the medication
metabolism, decreasing the concentration of the "parent drug" while increasing the
metabolite production. The half-life of the inducing drug may cause a delay before enzyme
activity increases. A decease in concentration of a medication metabolized by CYP2C9