Drugs, Drugs, and more Drugs

Question 1

What mineral(s) can interact with digitalis (digoxin) and alter therapeutic dose?

Answer 1

Magnesium* (alter absorption) and Potassium and Calcium

Question 2

MOA of Albuterol

Answer 2

Short acting beta agonist (SABA) (bronchospasm in asthma & COPD)

Question 3

MOA of Theophylline

Answer 3

Methylxanthine - bronchodilation via inhibition of phosphodiesterase (enzyme that breaks down cAMP) (bronchial asthma)

Question 4

Side effects (SE) of Albuterol

Answer 4

Tachycardia, tremors, shakiness, nervousness
Hyperkinesis
HA, insomnia
N/V, reactive bronchospasm

Question 5

SE of Theophylline

Answer 5

N/V/D
HA, insomnia, irritability, restlessness
Palpitations, tachycardia, hypotension

Question 6

Dosing of slow Digitalis (Digitoxin, Digoxin, Leaf)

Answer 6

Digitoxin: 0.2 mg BID x 4 days then maintenance dose
Digoxin: 0.25 mg until desired effect then maintenance dose
Digitalis Leaf: 100 mg BID-TID until therapeutic response in 7-10 days then maintenance dose

Question 7

Maintenance dose of Digitalis leaf, Digitoxin

Answer 7

Digitalis leaf: 100 mg per day

Digitoxin: 0.15 mg daily (MC)

Question 8

Dosing of rapid Digitoxin, Digoxin, Digitalis Leaf

Answer 8

Digitoxin: 0.6 mg, 0.4 mg, 0.2 mg q2-6 hrs
Digoxin: single dose of 0.5-0.75 mg
Digitalis Leaf: 1.2-1.8 g in 4+ divided doses q 4-6 hrs x 24-48 hrs until therapeutic response or toxicity

Question 9

Monitor digitalis Tx?

Answer 9

Range of 1.5-2 is ideal

Draw blood 5-6 hrs after last dose into non-serum separated red top tube