Life Span

Question 1

Pregnancy pharmacokinetic changes

Answer 1

Prolonged gastric transit time
Change in gastric pH
Decrease gastric tone and mobility
Increased absorption through skin, lungs, mucous membranes
Distribution of fat soluble drugs
Altered protein binding
Half like prolonged
Hepatic metabolism increased
Drug excreted rapidly

Question 2

Pregnancy class drugs

Answer 2

A, B, C, D, X
Try to avoid meds until after 1st trimester
A- safe for use in pregnancy, fetal harm appears remote, ex-levothyroxine, folic acid
B-no demonstrated animal risk in study but no adequate or well controlled studies in pregnant women, animal study shows adverse effects but not confirmed in humans, ex-acetaminophen, amoxicillin, metformin, NPH insulin, insulin aspart, cimetidine
C-animal studies relegated tetrogenic and AE on fetus no adequate human studies, risk vs benefit, ex-Albuterol, cipro, furosemide, propranolol, labetalol, pseudoephedrine, trazadone
D-positive evidence of human fetal risk in studies, benefits may justify risk, ex-etoh, Pheytoin, warfarin, reserpine, propylthioracil, levophed, thiazide, lithium, tetracycline
X-well observed studies in animal and humans show fetal anomalies, DO NOT USE, ex-estrogen, progestins, misoprostol, warfarin, statin, accutane, ACEs, thalidomide, cocaine, anticancer drugs

Question 3

Herbals in pregnancy

Answer 3

Unsafe- saw palmetto, goldenseal, dong quai, ephedra, yogimbe, black cohosh, Roman chamomile, St. John’s wort
Safe- red raspberry leaf, peppermint leaf, ginger root, slippery elm bark; psyllium, garlic, capsicum

Question 4

Ok drugs in pregnancy

Answer 4

Tylenol, PCN or cephalosporin, methyldopa, labetalol, nifedipine, calcium antacids, H2 Antagonist, PPI? Unsure data, B6, meclizine, diphenhydramine, metoclopramide

Question 5

Lactation considerations

Answer 5

Drugs contraindicated-amphetamines; cocaine, heroin, MJ, anticancer drugs, nicotine, lithium, methotrexate, ergotamine
Avoid ER drugs
Take meds after breastfeeding
Ok to take-beclomethasone, fluticasone, HCTZ, metoprolol, Zoloft, Paxil, insulin, glyburide, glipizide, dilantin, tegretol, ibuprofen, Tylenol, codeine, cromolyn, singular, barrier or progestin only for contraception

Question 6

Pediatric pharmacokinetics

Answer 6

Neonates/infants- immature circulation, increased gastric pH, increased gastric emptying time, decreased bile acids, immature BBB, less protein binding, immature liver-lack enzyme to metabolism until age 1, high half life, antibiotics and analgesics excreted slowly
Consider age, weight, surface area

Question 7

Age groups

Answer 7

Neonates-birth to one month
Infants- 1 mth to 2 years
Children-2 years to 12 years
Adolescent-12 to 18 years

Question 8

Clark’s formula (peds)

Answer 8

Dose=weight in pounds (divided by 150) X average adult dose

Question 9

Frieds formula (peds)

Answer 9

Dose=age in months (divided by 150) X average adult dose

Question 10

Young’s formula (peds)

Answer 10

Dose=age in years (divided by age + 12) X average adult does

Question 11

Adverse effects on drugs in peds

Answer 11

ASA, chloramphenicol, oral glucocorticoids, fluriquinalones, tetracycline

Question 12

Geriatric considerations

Answer 12

Absorption is slower, peak concentrations may be lower or delayed except with drugs with extensive first pass then may increase serum concentrations because less drug is extracted by the liver, smaller with reduced blood flow
Enteral feedings can interfere with absorption
Increased gastric pH
Low body water lower volume distribution
Low lean mass
High fat stores
Decreased plasma binding
Aging decreases liver/renal flow and therefore clearance

Question 13

Cockroft gault equation (Geri)

Answer 13

(Weight in kg) (140-age)
Divided by (72)(stable serum creatinine)
X 0.85 if female

Question 14

Beers criteria (Geri)

Answer 14

Intended to improve drug selection and reduce exposure to potentially inappropriate medications in older adults
Drugs to avoid, drugs to avoid in patients with specific disease or syndromes, drugs to use with caution, selected drugs whose dose should be adjusted based on kidney function, selected drug drug interactions

Question 15

Commonly overprescribed and inappropriate used drugs (Geri)

Answer 15

Androgens/testosterone
Anti infective agents
Anticholinergics
Urinary and GI antispasmodic
Antipsychotics
Benzos
Non benzo hypnotics
Digoxin as first line for AF/CHF
Dipyridamole
H2 receptor antagonist
Insulin SS
NSAIDs
PPI
Sedating antihistamines
Skeletal muscle relaxants
TCAs

Question 16

Commonly under prescribed drugs (Geri)

Answer 16

ACEI for DM, proteinuria
ARBs
Anticoagulant
Antihypertenivses and diuretics for uncontrolled HTN
BB for MI or CHF
bronchodilators
PPI, Misoprostol for GI protection from NSAIDs
Statins
Vitamin D and calcium for those at risk for osteoporosis

Question 17

Risk factor for ADE (Geri)

Answer 17

6 or more concurrent chronic conditions
12 or more doses of drug per day
9 or more mediations
Prior adverse drug events
Low body weight or BMI
Age 85 or older
Estimated crcl less than 50

Question 18

ADE Drugs (Geri)

Answer 18

ACEI with MRA-hyperkalemia
Anticholinergics with anticholinergics-cognitive decline
CCB, with azithromycin or clarithromycin-hypotension or shock
Concurrent use of 3 or more active CNS drugs-falls and fractures
Digoxin plus erythromycin, clarithyromycin, azithromycin-digoxin toxicity
Lithium plus loop diuretic or ACEI-lithium toxicity
Peripheral alpha blockers plus loop diuretic-urinary incontinence in women
Pheytoin and SMX/TMP- phenytoin toxicity
Sulfa plus SMX, TMP, cipro, levofloxacin, erythromycin, clarithromycin, azithromycin, cephalexin-hypoglycemia
Tamoxifen and paroxetine or other CYP2D6 inhibitor-results in increased breast CA death due to inactivity of tamoxifen
Theophylline and ciprofloxacin-theophylline toxicity
Trimehoprim with ACEI, ARB, MRA- hyperkalemia
Warfarin with cipro, levofloxacin, gatifloxacin, fluconazole, amoxicillin, cephalexin, amiodarone- elevated INR bleeding
Warfarin and NSAIDs-GIB

Question 19

Common drug disease interactions

Answer 19

Obesity alters volume of distribution in lipophilic drugs
Ascites alters volume of distribution of hydrophilic drugs
Dementia can increase sensitivity, induce paradoxical reactions to drugs with CNS or anticholinergics activity
Renal or hepatic impair detox and excretion of drugs

Question 20

How to Rx for Geri patients

Answer 20

Starts low titrate slow
Avoid starting two drugs at same time