Oc Pharm 1 (Prescribing in Peds & Elderly)

What does a lower number of drug metabolism enzymes in a newborn lead to?

drug accumulates in blood stream

How does topical skin absorption vary in children compared to adults?

children have thinner and more porous skin

Up to what age do children absorb drugs topically better than adults?

6 yo

What can lead to better topical absorption of drugs in all ages?

if skin disrupted

How do topical drugs reach systemic circulation?

conjunctival and nasal mucous membranes

What are characteristics of topical absorption into the systemic circulation?

no first pass metabolism and is directly into systemic circulation

What percent of a topical drug applied to the conjunctival sac may diffuse into the systemic circulation?

80%

A topical medication applied to the conjunctival sac diffuses into the systemic circulation via the _____________________.

highly vascularized nasopharyngeal

In neonates, gastric acid secretion and peristalsis are ____________ which can change the absorption rate of some drugs.

reduced

How does the GI tract of a neonate compare to an adults?

poor barrier to drug absorption

How does the amount of extracellular water in newborns and infants compare to that of an adult?

they have more ~70-75% of body weight but adults have ~20%

What is important to about the blood brain barrier in newborns?

it is incomplete

How is the binding of drugs different in newborns younger than 6 months?

they have less plasma available for binding leading to increased amounts of unbound drugs

What is common in newborns which can further the amount of unbound medication in the blood?

higher level of bilirubin

What can accelerate other side effects?

dehydration

What are the effects of dehydration?

decreased rate of excretion of drug, increased bioavailability of drug and risk of toxicity

What up to what age should dosing adjustments be made for renal function?

1-2 yo

What characteristics of children lead to increased drug toxicity?

smaller bodies, better absorption, impaired metabolism, decreased drug elimination, more available drug in blood streem

What conversion is used to calculate drug dosage for children?

20-50 mg/kg for weight of child

1 kg = _____lb

2

1 tsp = _____ ml

5

Which aminoglycoside is safe in children 2mo and older for superficial ocular infections?

Tobramycin

Which macrolide is safe in all ages for superficial ocular infections and prophylaxis of ophthalmia neonatorum?

Erythromycin

Which polypeptide medications are safe in all ages for ophthalmic infections?

Bacitracin, Polymyxin B, polysporin

Which antibiotic is safe in children 2mo and older for superficial ocular infections?

Polytrim

Which fluoroquinolone is safe in children 4mo and older for bacterial conjunctivitis?

Moxifloxacin

Which topical antibiotic medication is effective against gonorrhea and blepharitis?

Bacitracin

Which antibiotic has a risk of Stevens Johnson syndrome and stings?

Sulfacetamide

Which antibiotic is used in infants and is for select situations/organisms?

Erythromycin

Which antibiotic is a pregnancy category B and iseffective against chlamydia and N. Gonorrhea?

AzaSite

Which antibiotic is safe in pediatrics but has too frequent dosing for children in school?

Polytrim

Which antibiotic is effective and good for children ung although it is not approved for children?

Polysporin

Which aminoglycoside is good to use in children but need to watch for an allergic reaction?

tobramycin

Which antibiotic has an ADR of teeth staining and issues with bone growth?

tetracyclines

Which antibiotic is responsible for gray baby syndrome?

chloramphenicol

Which antibiotics are resistant to staph and can be considered for children under 6 yo?

ciprofloxacin and ofloxacin

Which medications are considered safe in the treatment of bacterial conjunctivitis in postneonatal to 1 yo?

Erythromycin, polytrim, moxeza, tobrex

Which medications are good for the treatment of bacterial conjunctivitis in preschool to school age children?

polysporin, tobramycin, moxeza, vigamox, besivance, AzaSite

What are ADRs of Visine in children?

drowsiness and bradycardia

What medication can be used in allergic conjunctivitis in children?

NSAIDs

Which medication can be used as a substitute for a steroid in the treatment of vernal allergic conjunctivitis?

cyclosporin and tacrolimus (Calcineurin inhibitors)

How is passive diffusion (bioavailability) of drugs affected by aging?

unchanged

How is active transport and first-metabolism affected by aging?

decreased

With age, the volume of distribution of water soluble drug _____________ leading to ____________ plasma concentration.

decreases; increased

With age, the volume of distribution of lipid soluble drug _____________ leading to ____________ effects of the drug.

increases; longer

How is renal function affected by aging?

decreased glomerular filtration rate, loss of glomeruli and renal mass, and decreased renal blood flow

What are implications of reduced drug excretion in geriatric patients?

prolonged half-life, drug accumulation, increased sensitivity to drugs

Which medications having guidelines for dosing adjustments in patients with altered renal excretions?

acyclovir, valacyclovir, ciprofloxacin