What is mg kg day

Now we need to find something to put on the right side of the equation that will help us determine a safe dosage for this patient. Since the dosage range depends on the patient's weight, we begin by putting 6 kg to the right of the equals sign, because we need to find the number of mg we need for a 6 kg patient:.

We can put 6 kg over 1 without changing it: 6 kg 1. If we look at the label, we see that it says that the safe dosage is mg per kg per day. Because this safe dosage is given per day , we should label our calculations "Safe dosage per day":.

Now we want to get rid of the kg on the top of the right side of the equation, and we notice that we can write mg per kg as a fraction: mg 1 kg. In a safe dosage, mg and 1 kg should be equal; we can multiply our equation by mg 1 kg , because: The top of this fraction will be equal to the bottom in a safe dosage.

This fraction has kg on the bottom, which will cancel out the kg we want to get rid of on the top. None of the numbers will cancel, but we can cancel units that appear on both the top and the bottom to get:. Is the following order safe for a 43 lb child? This child has a moderate infection. Order: Kefzol mg IM q. Since the dosage range depends on the patient's weight, we begin by putting 43 lb to the right of the equals sign, because we need to find the number of mg we need for a 43 lb patient:.

We can put 43 lb over 1 without changing it: 43 lb 1. Since the patient's weight is in lb and we want to use metric as a general rule, we need to convert lb to kg. If we look at the label, we see that it says that the safe dosage is 25 to 50 mg per kg per day. We choose this concentration instead of the others listed on the label because it is the one the label says we should use when This child has a moderate infection.

Because this safe dosage is given per day , we should label our calculations "Safe dosage per day", and because the safe dosage given is a range , our answer must be a range , too, with a minimum safe amount, and a maximum safe amount:. Now we want to get rid of the kg on the top of the right side of the equation, and we notice that we can write mg per kg as two different fractions: 25 mg 1 kg and 50 mg 1 kg. In a minimum safe dosage, 25 mg and 1 kg should be equal and in a maximum safe dosage, 50 mg and 1 kg should be equal; we can multiply our equation for the minimum by 25 mg 1 kg and our equation for the maximum by 50 mg 1 kg , because: The top of these fractions will be equal to the bottom in a safe minimum or maximum dosage.

Both fractions have kg on the bottom, which will cancel out the kg we want to get rid of on the top of each equation.

Now we need to get rid of the decimal in 2. If we multiply 2. Now we notice that we can divide both 10 and 22 by 2, so we can reduce the right side of our equations by dividing 10 on the top and 22 on the bottom by The ordered amount is safe , because the ordered amount of mg is within the safe range per dose mg. Is the following order safe for a lb child? Order: Mithracin mcg IV q. We want our answer to be in mcg, because our goal is to calculate the safe dosage and compare it to the given order , which measures the drug in mcg.

Since the dosage range depends on the patient's weight, we begin by putting lb to the right of the equals sign, because we need to find the number of mcg we need for a lb patient:. We can put lb over 1 without changing it: lb 1. If we look at the label, we see that it says that the safe dosage is 25 to 30 mcg per kg per day.

Now we want to get rid of the kg on the top of the right side of the equation, and we notice that we can write mcg per kg as two different fractions: 25 mcg 1 kg and 30 mcg 1 kg. In a minimum safe dosage, 25 mcg and 1 kg should be equal and in a maximum safe dosage, 30 mcg and 1 kg should be equal; we can multiply our equation for the minimum by 25 mcg 1 kg and our equation for the maximum by 30 mcg 1 kg , because: The top of these fractions will be equal to the bottom in a safe minimum or maximum dosage.

The ordered amount is unsafe , and we should check with the physician who wrote the order and should not give the patient this dose, because the ordered amount of mcg is not within the safe range per dose mcg. Is the following order safe for a 35 lb child?

Order: Velocef mg IV q. Since the dosage range depends on the patient's weight, we begin by putting 35 lb to the right of the equals sign, because we need to find the number of mg we need for a 35 lb patient:. We can put 35 lb over 1 without changing it: 35 lb 1. If we look at the label, we see that it says that the safe dosage is 50 to mg per kg per day. Now we want to get rid of the kg on the top of the right side of the equation, and we notice that we can write mg per kg as two different fractions: 50 mg 1 kg and mg 1 kg.

In a minimum safe dosage, 50 mg and 1 kg should be equal and in a maximum safe dosage, mg and 1 kg should be equal; we can multiply our equation for the minimum by 50 mg 1 kg and our equation for the maximum by mg 1 kg , because: The top of these fractions will be equal to the bottom in a safe minimum or maximum dosage.

Is the following order safe for a 33 kg child? This child has bacterial meningitis. Order: Zinacef 2. We want our answer to be in g, because our goal is to calculate the safe dosage and compare it to the given order , which measures the drug in g.

Since the dosage range depends on the patient's weight, we begin by putting 33 kg to the right of the equals sign, because we need to find the number of g we need for a 33 kg patient:. We can put 33 kg over 1 without changing it: 33 kg 1. If we look at the label, we see that it says that the safe dosage is to mg per kg per day. We choose this concentration instead of the others listed on the label because it is the one the label says we should use when This child has bacterial meningitis.

Now we want to get rid of the kg on the top of the right side of the equation, and we notice that we can write mg per kg as two different fractions: mg 1 kg and mg 1 kg. In a minimum safe dosage, mg and 1 kg should be equal and in a maximum safe dosage, mg and 1 kg should be equal; we can multiply our equation for the minimum by mg 1 kg and our equation for the maximum by mg 1 kg , because: The top of these fractions will be equal to the bottom in a safe minimum or maximum dosage.

Now we notice that the units we have on the top right of our equation are mg, but we need our answer to be in g. The ordered amount is safe , because the ordered amount of 2.

Calculating Dosages Based on Body Surface Area Sometimes using a person's weight to determine how much of a drug they receive isn't the best method. For example, someone who is 4 ft 10 in tall and someone who is 6 ft 4in tall might both be lbs, but they may need more or less of a drug, depending on what portion of their weight is fat, or muscle, or retained fluid, etc. Some ways of dealing with this might include determining a person's dosage not on their actual weight, but on their "ideal" body weight - the weight that would be healthy for someone of their height and build; a hospital should have a chart that would allow us to calculate what this is.

However, another way to address this issue is to determine how much drug a person should get by their body surface area, rather than their weight. The body surface area is precisely what it sounds like: the surface area of a person's body.

You have probably calculated the surface areas of more regular shapes, like cubes and balls and pyramids in a previous math class. Pediatric Dosage Calculations [Internet]. In: Davis's Drug Guide. Pediatric Dosage Calculations General. Your free 1 year of online access expired.

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A Davis's Drug Guide subscription is required to. Already have an account? The number of days supply can be calculated by dividing the number of capsules dispensed by the number of capsules used per day. Since this prescription calls for 2 puffs four times a day, this patient will be using 8 inhalations per day.

Dosing in Special Cases. Geriatric patients often require special consideration when designing dosage regimen. Pediatric patients are not just little adults but need pediatric doses. There are also general rules for calculating an infant's or child's dose of medication when given the age or weight of the patient and the normal adult dose.

These general rules are not drug - specific and should only be used in the absence of more complete information. It is the duty of pharmacists to be knowledgeable about the limitations of using set formulas or rules for calculating pediatric doses.

It is best to use dosing based on information in pharmacy reference books or package inserts. Jill weighs 42 pounds and is 43 inches tall. The prescriber wants to give Diazepam to Jill. What is an acceptable dose? Calculate the weight in kg of Jill: Calculating Weight in kg Body Surface Area BSA is based on Jill's weight and height and is read from a nomogram nomograms for adults and children are included.

Find the patient's weight in pounds or kilograms on the right hand side of the nomogram. Find the patient's height in inches or centimeters on the left hand side of the nomogram. Draw a straight line connecting these two points and red the BSA in m2 at the point the line intersects with the middle line.

Calculation of dose: Calculating Dose Calculation of dose using normal adult dose and "rules" for pediatric doses based on the child's weight or age. The prescriber wants to give Captopril to Tom.

What is an acceptable dose of Captopril for Tom? Initial: Oral,