2. Digoxin

Question 1

Bioavailability

Different dosage form have a different bioavailability.

Elixir
Liquid, tablet and IV

Answer 1

Liquid: 75%
IV: 100%
Tablet: 50-90%

Question 2

Digoxin

Range in blood

Normal and toxic

Answer 2

Normal: 0.7-2mcg/L

Toxic: 2-3mcg/L

Question 3

Digoxin

Dose
AF
and HF

Answer 3

AF: 125-250mcg

HF: 62.5-125mcg

Question 4

Digoxin

Bloods tested when

Answer 4

6hrs after loading dose

During tx no need for blood test

Unless toxic

Question 5

Digoxin

Secreted where?

Answer 5

Renal secreted 70%

Reduce dose, monitor

Question 6

Compare dose
Digoxin

AF and Arrhythmia

Answer 6

HF is HALF the dose of in Arrhythmia

Question 7

Digoxin

SE

Answer 7

Report to dr STAT

NV
Diarrhoea 
Dizzy 
Confusion 
General unwell 
Skin rash 
Headache 
Blurry, yellow vision
Abdominal pain
Delirium

Question 8

Digoxin

Monitoring (4)

Answer 8

1. Serum electrolytes
   K,Mg,Ca
2. Renal function
   (Reduce dose if impaired

3.plasma digoxin
(6hrs after LD)

4. Heart rate maintained at 60 bpm

Question 9

Digoxin

Interaction

(4)

CRASED

Answer 9

1. Reduced plasma concentration with
   At johns wort
2. Drugs impairing renal function:
   NSAIDs
   ACE/ARB

3.LOOP DIURETIC (Enz inducers), thiazides, rifampin
Acetazolamide, amphotercin
As they can cause Reduced K+ this can cause digoxin toxicity.

4.CRASED
CCB(veramapil, dilitiazam)
Rifampicin 
Amiodarone 
St. John’s wort
Erythromycin 
Diuretics

Question 10

Digoxin not given if heart rate is

Answer 10

Less than 60 beats per minute

Question 11

Digoxin

Increase plasma concentration with (10)

Answer 11

Amiodarone 
Verapamil 
Dilitiazem 
Ciclosporin
Quinine 
Nifedipine 
Itraconazole
Spironolactone
Mirabegron
Alprazolamaiodarone

Question 12

Digoxin

Risk of hypOkalaemia 4

Answer 12

Loop Diuretics
Thiazides
Acetazolamide
Amphotericin

Question 13

Digoxin

Decreased plasma concentration with

Answer 13

At johns wort

Question 14

Digoxin is contraindicated in

A disease which is described as follows:

is a relatively common heart condition that causes the heart to beat abnormally fast for periods of time. The cause is an extra electrical connection in the heart

Which disease is this? And digoxin should never be given in this case

Answer 14

Wolff-Parkinson-White (WPW) syndrome

Question 15

Digoxin MOA

Answer 15

Digoxin increases the force of contraction of the muscle of the heart by inhibiting the activity of an enzyme (ATPase) that controls movement of calcium, sodium, and potassium into heart muscle. Calcium controls the force of contraction.

Question 16

Digoxin

SE is colour vision what colour and what is the medical name?

Answer 16

Yellow

Xanthopsia

Is a color vision deficiency in which there is a predominance of yellow in vision due to a yellowing of the optical media of the eye. The most common cause is digoxin’s inhibitory action on the sodium pump, and the development of cataracts which can cause a yellow filtering effect