Question

The Patient must receive Benadryl of 40mg IM t.i.d. The vial is labeled 50mg/mL. How many mL will you administer to the patient?

A patient is to receive Pitressin (Vasopressin) 10 units. I.M q8h. If the label reads 20 units/mL. How many mL of this hormonal drug will you administer?

Answer 1

Q1.

Answer.

Order dose = 40 mg

Available dose = 50 mg/ ml

Use the formula,

Desire dose = ( ordered dose / available dose) x available volume in ml

= ( 40 mg / 50 mg ) x 1 ml

= 0.8 x 1ml

= 0.8ml

Hence 0.8 ml/ single dose should be administer per one dose.

(To calculate for one day, multiple the 0.8ml by 3 , that is 2.4 ml / day)

Q2.

Answer.

Ordered dose = 10 unit

Available dose = 20 unit/ ml

Same formula can apply,

Desire dose = ( ordered dose/available dose) x available volume in ml

= (10 unit/ 20 unit) x 1 ml

= 0.5 x 1 ml

= 0.5 ml

Hence 0.5 ml/single dose should be administer.

For whole day calculation, multiply the desire dose by 3 ( because the drug frequency is q8h means 3 times a day)

= 0.5 x 3

= 1.5 ml/ day

Hence 1.5/ day can be administer.