Naplex calculation formulas

[rxglasshalffull]

Advertisement - Members don't see this ad

Hi SDN,

I am taking the NAPLEX in 10 days and was wondering if we need to memorize the formulas for the calculation part, I am not talking about CrCl I am talking about E value, TEE, BEE, very specific formula like that. Thank you!

 

[RxLouie88]

If you watch the video for RxPrep- shapiro even said, "you can ask any pharmacist working at the hospital and no one remembers the BEE".

However, that said, you should at least know how to calculate them right? Better safe than sorry. As for my experience I didn't have any calculations in my exam version. But the E-vaule- yes.

As far as memorizing...Don't, but make sure you know how to solve them because when you're taking the test, your nerves can sometimes make you read the questions differently...just practice over and over and you should be fine.

 

[rxglasshalffull]

If you watch the video for RxPrep- shapiro even said, "you can ask any pharmacist working at the hospital and no one remembers the BEE".

However, that said, you should at least know how to calculate them right? Better safe than sorry. As for my experience I didn't have any calculations in my exam version. But the E-vaule- yes.

As far as memorizing...Don't, but make sure you know how to solve them because when you're taking the test, your nerves can sometimes make you read the questions differently...just practice over and over and you should be fine.

thank you, im taking the naplex in 9 days and my nerves....omg im freaking out..maybe unnecessarily.

 

[pillpharmer]

I typed up a formula sheet for the NAPLEX if you'd like a copy. PM me.

 

[pillpharmer]

Since so many people have asked for my formula sheet, I'll just post it on here. Good luck to everyone taking the test.

Naplex Formula Sheet

Conversions between units
1 grain = 65mg
1mg aminophylline = (0.8)(mg theophylline)

Waist Circumference Risk
>35 inches for women
>40 inches for men

BMI = [weight (kg)]/[height (m^2)] OR BMI={[weight (lbs)]/[height (in^2)]} X 704.5

IBW (male) = 50kg + (2.3kg)(inches>5ft)
IBW (female) = 45.5kg + (2.3kg)(inches>5ft)

If BUN/SCr ratio > 20, consider dehydration in the patient.

Cockcroft-Gault Equation
CrCl = (140-age in yrs)(wt in kg)/(72)(SCr) If female, multiply answer by 0.85

Specific Gravity
SG = weight (g)/volume (mL)

Body Surface Area
BSA (m^2) = sqrt{[ht (cm)][wt(kg)]/3600}

Half Life
T1/2 = 0.693/k

TPN Kcal
Dextrose 3.4kcal/g
Amino Acids 4kcal/g
Lipids 9kcal/g
10% Lipid emulsion 1.1kcal/g
20% lipid emulsion 2kcal/g
Glucose 4kcal/g

Fluid Needs Daily
Wt >20kg: 1500mL + 20mL[(wt in kg) – (20kg)]

Basal Energy Expenditure (BEE) (Harris-Benedict Equation)
Male: 66.47 + 13.75(wt in kg) + 5(ht in cm) – 6.76 (age in years)
Female: 655.1 + 9.6(wt in kg) + 1.85(ht in cm) – 4.68(age in years)
BEE estimate: 15-25kcal/kg (to double check equation)


Total Energy Expenditure (activity and stress factors will be given)
TEE = (BEE)(activity factor)(stress factor)

Nitrogen Balance
1g nitrogen = 6.25g protein
Nitrogen Intake = (grams protein)/6.25

Corrected Calcium (use when Albumin < 3.5)
Corrected Calcium = (Serum calcium) + [(4-albumin)(0.8)]

Osmolarity
mOsmol/L = [(concentration of substance in g/L)/(MW in g/mol)] (# of species)(1000)

Sodium Chloride Equivalent (E Value)
E = (58.5)(i)/(MW of drug)(1.8) i = dissociation factor

Mol = g/MW mmol = mg/MW

mEq = (mg)(valence)/MW OR mEq = (mmol)/(valence)

Temperature Conversion
F = (C)(9/5) + 32

Absolute Neutrophil Count (ANC) Normal limites 2200-8000
ANC = (WBC)(% neutrophils) (% neutrophils) = segs + bands

Anion Gap (High is >12mEq/L = gap acidosis)
AG = Na &#8211; (Cl + HCO3)

Henderson Hasselbach equation
Weak Acid
pH = pka + log (salt/acid)

Weak Base (pkw IS ALWAYS 14)
pH = pkw &#8211; pkb + log(base/salt) OR pH = pka + log (base/salt)

Aliquot Measurement
Mean Weighable Quantity (MWQ) = (sensitivity requirement SR)/ (% of error)

Relative Risk (RR)
RR = (exposed or treated group event)/(nonexposed or placebo group event)
RR <1 reduces risk of event occurrence with treatment
RR = 1 no reduction of risk between treatment vs. nontreatment group
RR > 1 increases risk of event occurrence with treatment

Relative Risk Reduction (RRR)
RRR = [(%event occurrence of control or placebo)(% event occurrence of treatment)]/(% event occurrence control or placebo)
RRR = 1-RR (relative risk)

 

[pillpharmer]

Accidental double post

 

[rxglasshalffull]

thank you!

 

[supharma]

Thanks a bunch, you are a star.

 

[rxglasshalffull]

Since so many people have asked for my formula sheet, I'll just post it on here. Good luck to everyone taking the test.

Naplex Formula Sheet

Conversions between units
1 grain = 65mg
1mg aminophylline = (0.8)(mg theophylline)

Waist Circumference Risk
>35 inches for women
>40 inches for men

BMI = [weight (kg)]/[height (m^2)] OR BMI={[weight (lbs)]/[height (in^2)]} X 704.5

IBW (male) = 50kg + (2.3kg)(inches>5ft)
IBW (female) = 45.5kg + (2.3kg)(inches>5ft)

If BUN/SCr ratio > 20, consider dehydration in the patient.

Cockcroft-Gault Equation
CrCl = (140-age in yrs)(wt in kg)/(72)(SCr) If female, multiply answer by 0.85

Specific Gravity
SG = weight (g)/volume (mL)

Body Surface Area
BSA (m^2) = sqrt{[ht (cm)][wt(kg)]/3600}

Half Life
T1/2 = 0.693/k

TPN Kcal
Dextrose 3.4kcal/g
Amino Acids 4kcal/g
Lipids 9kcal/g
10% Lipid emulsion 1.1kcal/g
20% lipid emulsion 2kcal/g
Glucose 4kcal/g

Fluid Needs Daily
Wt >20kg: 1500mL + 20mL[(wt in kg) – (20kg)]

Basal Energy Expenditure (BEE) (Harris-Benedict Equation)
Male: 66.47 + 13.75(wt in kg) + 5(ht in cm) – 6.76 (age in years)
Female: 655.1 + 9.6(wt in kg) + 1.85(ht in cm) – 4.68(age in years)
BEE estimate: 15-25kcal/kg (to double check equation)


Total Energy Expenditure (activity and stress factors will be given)
TEE = (BEE)(activity factor)(stress factor)

Nitrogen Balance
1g nitrogen = 6.25g protein
Nitrogen Intake = (grams protein)/6.25

Corrected Calcium (use when Albumin < 3.5)
Corrected Calcium = (Serum calcium) + [(4-albumin)(0.8)]

Osmolarity
mOsmol/L = [(concentration of substance in g/L)/(MW in g/mol)] (# of species)(1000)

Sodium Chloride Equivalent (E Value)
E = (58.5)(i)/(MW of drug)(1.8) i = dissociation factor

Mol = g/MW mmol = mg/MW

mEq = (mg)(valence)/MW OR mEq = (mmol)/(valence)

Temperature Conversion
F = (C)(9/5) + 32

Absolute Neutrophil Count (ANC) Normal limites 2200-8000
ANC = (WBC)(% neutrophils) (% neutrophils) = segs + bands

Anion Gap (High is >12mEq/L = gap acidosis)
AG = Na – (Cl + HCO3)

Henderson Hasselbach equation
Weak Acid
pH = pka + log (salt/acid)

Weak Base (pkw IS ALWAYS 14)
pH = pkw – pkb + log(base/salt) OR pH = pka + log (base/salt)

Aliquot Measurement
Mean Weighable Quantity (MWQ) = (sensitivity requirement SR)/ (% of error)

Relative Risk (RR)
RR = (exposed or treated group event)/(nonexposed or placebo group event)
RR <1 reduces risk of event occurrence with treatment
RR = 1 no reduction of risk between treatment vs. nontreatment group
RR > 1 increases risk of event occurrence with treatment

Relative Risk Reduction (RRR)
RRR = [(%event occurrence of control or placebo)(% event occurrence of treatment)]/(% event occurrence control or placebo)
RRR = 1-RR (relative risk)

The formula sheet that you posted, first of all, thank you. im still confused whether we need to MEMORIZE all the formulas, or they are given on the exams.

 

[ladiwag]

NO formulas were given on my exam. I memorized all the formulas above and more except for the BEE. It didn't make sense to me to memorize the BEE.

 

[OleMissRx]

NO formulas were given on my exam. I memorized all the formulas above and more except for the BEE. It didn't make sense to me to memorize the BEE.

Was valence or number of species provided for mEq and milliosmols?

 

[ladiwag]

Was valence or number of species provided for mEq and milliosmols?

No.

 

[yari1305]

thanks a lot! I guess I will memorize the valence numbers, Im getting confused in those problems.