Pharm. Special patients groups Flashcards
Targeted special groups in pharm
Pregnancy
Lactation
Pediatrics
Geriatrics
Which two groups have a scarce amount of data about pharmacokinetics/pharmacodynamics and why?
Infant/child populations and pregnant women because nobody is willing to risk that patient population for research.
FDA preganancy medication categories
A B C D X
A class medication
Remote possibility of fetal harm
No risk of fetal harm demonstrated in controlled trials
B class medicaiton
Animal studies have not demonstrated fetal harm, but human studies have not been done.
Or Animal studies have demonstrated some fetal harm but human studies have been done with no evidence of harm
C class medication
Animal studies have demonstrated potential fetal harm, but there are no controlled trials to confirm the event in humans
D class medication
Evidence of fetal risk has been demonstrated in humans, but use may be justified in some cases based on benefit:risk
X class medication
Teratogens
Studies in animals or humans have demonstrated significant fetal harm or deformation.
Completely contraindicated in women who are pregnant
Pregnancy pharmacokinetic changes to oral medications
Decreased gastric motility and gastric secretions
Nausea and vomiting
Pregnancy pharmacokinetic changes to transdermal medications
increased blood flow (peripheral vasodilation)
Increased body water
Pregnancy pharmacokinetic changes to pulmonary sytem
Cardiac and tidal volumes are increased by approximately 50% = hyperventilations and increased pulmonary blood flow
Pregnancy pharmacokinetic changes to distribution
Increased blood volume (30-50%)
INcreased adipose deposition
Decreased albumin concentration
Pregnancy pharmacokinetic changes to metabolism
Induced and inhibited CYP enzyme activity related to estrogen and progesterone levels
Pregnancy pharmacokinetic changes to elimination
Increased renal blood flow
Pregnancy pharmacokinetic changes summary
Changes are rarely clinically significant as dosage adjustments are not typically warranted and difficult to predict
Epilepsy in pregnancy
Treatment options are limited as all the medications are harmful to the fetus.
Valproic acid is the only medication that is always stopped during pregnancy.
Potential adverse effects noticed in the infant following passive exposure from lactation
Drowsiness/sedation (Analgesics, antihistamins, antidepressants, anti-epileptics)
Diarrhea (antibiotics)
Withdrawal symptoms (antidepressants, nicotine, drugs of abuse)
Pharmacotherapy techniques in lactation
Minimizing exposure to the infant (breast feeding during a trough in the medication regimen)
Avoid unnecessary medications
Coordinate medications and feeding schedules (pump and dump schedule)
What drugs inhibit prolactin which inhibit lactation?
Oral contraceptives, levadopa, repinirole
Why can’t pediatric pharmacology be simplified to small adult principles?
Because children are not small adults! many physiological differences.
Geriatric pharmacology population
Adults > 65 yo comprising 13% of the population
it is a growing population
Geriatric pharmacokinetic elimination consideration
REduced muscle mass may exaggerate creatinine clearance calculations. (may not have any muscle mass)
Beers criteria
Evidence based approach for medications used in elderly populations
STOPP criteria
Screening tool of older persons with potentially inappropriate prescriptions
Polypharmacy
Complex drug regimens
Strategies to avoid polypharmacy
Education, reinforcement, education!
Review medication profile routinely
Allergies as an adverse event
Immune-mediated response to certain chemical substances
No way of predicting initial reaction
Side effects as an adverse event
Medications have side effects!
Predictable
May be caused via same or different mechanism as therapeutic use of drug
Adverse drug reaction
Unintended noxious response to a drug when used at normal doses for usual purposes
Cannot be predicted
Pregnancy summary
Changing kinetics throughout pregnancy
Exposure to fetus
Non-pharmacologic strategies must be considered
Minimal effective dose for the shortest duration
Use medications with the best safety profile
Risk:benefit
Lactation summary
Avoid unnecessary medications
Non-pharmacologic strategies must be considered
Coordinate medications with feeding schedule
Minimal effeective dose for the shortest duration
Risk:benefit
Monitor the infant for effects
Pediatrics
Not small adults!!
Diverse population
Changing pharmacokinetics
Consider age and weight for dosing
Use multiple resourses
Geriatrics
Sensitive to side effects
Beer’s criteria
STOPP criteria
Polypharmacy is a problem
