Home Forums Discussions General Discussion Calculating sigs for Peds and FP

I don't know why it took me 28 years to come up with this formula. Makes my life that much easier. So you are writing for amoxicillin suspension 400 mg/5mLs. Not sure why anyone would use the 250/5 or 125/5 as 400/5 still gives you a good sig amount.

Anyway, as everyone knows the dosing for an ear infection is 90 mg/kg/day divided bid. So, I would have an 11 kg kid and think 11 X 90 = 990 mg divided by 2 = around 495 mg bid = divided by 80 = 6.19 mLs bid. (Obviously you round it off)

But you can simply remember 0.56 (I suppose 0.55 is fine) times the kgs and you have the ~ same amount each time, i.e., 0.56 times 11 = 6.16 mLs. Works every time. You could do it with other sigs but I use 400 mg/5mLs so often, It saves you time and you will make less errors.

A little late to the response but..
Many meds fall into 1 teaspoon per 10 or 20 mg/kg

125/5 and 250/5 are supposed to be q 8 hour doses but I have seen ERs do q 12
Thus you are left with 400/5 (or 600/5 as well with augmentin)
dosing is 25-50 mg/kg/dose (amox, sl lower with augmentin)
This will roughly equal 1 teaspoon(5mL) per 10 kg / dose (40mg/kg)

acetaminophen (160/5) dosing is 10-15 mg per dose so 3-4 mL/10kg
(or for > 24# 1 tsp/10 kg multiples (1.5 for 36#)) (or 1 tsp per 12kg)

Ibuprofen (100/5) is 5-10 mg/kg so again 1 teaspoon (5ml) per 10 Kg

azithromycin 10mg/kg day 1 and 5mg/kg day 2-5 The most common formulation is 200mg/kg or
1 teaspoon per 20 kg

There are exceptions to this, of course but I have found this the easiest way to calculate drug doses