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math calculations with oral suspension (1)

What are the total quantity and the total days supply for the following Rx: Mycostatin susp #2 oz 1 mL po tid x 2 weeks ------------------------------------------------------------ The doctor has prescribed Mycostatin oral suspension, but the pharmacist will have to dispense the generic version Nystatin oral suspension. The doctor wants the pharmacist to dispense 2 ounces, that is, 60 mL This medicine was prescribed for a child. In this case, the regular size of the bottle is 60 mL So, the total quantity to be dispensed is 60 mL The sig says: give 1 mL by mouth three times daily for 14 days The total days supply is 14 days as stated by the doctor.

Calculate the total quantity and the total days supply for the following Rx: Zovirax (1 pint) 3 tsp po qid x 5 days ------------------------------------------------------------ The doctor has prescribed Zovirax 200mg/5mL oral suspension, but the pharmacist may very likely dispense the generic version acyclovir 200mg/5mL oral suspension. The sig says: take 3 teaspoonsful by mouth four times a day for five days Notice that 1 tsp is equal to 5 mL So, the total quantity to be dispensed will be 3 * 5mL * 4 * 5 which is 300mL But, the pharmacist will very likely dispense 1 pint because the doctor wrote 1 pint at the top of the prescription. Notice that 1 pint is equal to 473 mL On the other hand, some pharmacists may choose to dispense 300mL instead of 473mL. The decision is up to the pharmacist to choose which quantity to dispense. The days supply is 5 days as stated by the doctor.

Calculate the total quantity and the total days supply for the following Rx: Amoxicillin - Pot Clavulanate 600-42.9mg/5mL sig: 1 tsp bid for 10 days qty: 10 ------------------------------------------------------------ The doctor has prescribed Amoxicillin - Clavulanate Potassium 600mg/5mL oral suspension. This medication is the generic equivalent to Augmentin ES 600mg/5mL oral suspension. Augmentin is the brand-name drug. The sig says: take 1 teaspoonful by mouth twice daily for 10 days Notice that 1 tsp = 5 mL In turn, the patient will take 5 mL twice daily for 10 days, that is, the patient will take 5 * 2 * 10 which is 100. Therefore, the patient will take a total of 100mL But, this medicine is supplied in bottles of 75mL, 125mL, and 200mL There is no way for the pharmacist to dispense 100mL only. In turn, the pharmacist will dispense one bottle of 125mL So, the total quantity to be dispensed is 125 mL Now, the technician could re-write the sig directions: take 1 teaspoonful by mouth twice daily for 10 days. Discard the remainder. The total days supply is 10 days as stated by the doctor. Notice that the doctor wrote qty: 10, but this information is unnecessary and confusing. The sig codes are very clear and enough for the pharmacist to dispense the medication.

Calculate the total quantity and the total days supply for the following Rx: Suprax 100 mg / 5 ml sig: 130 mg po qd for 10 d ------------------------------------------------------------ The sig says: take 130 mg by mouth every day for ten days The doctor has prescribed an oral suspension and therefore we need to convert 130mg into mL In other words, how many milliliters (mL) there are in 130 mg We know that the ratio of Suprax is 100mg/5mL Notice that 100mg/5mL is the same as 5mL/100mg x / 130 mg = 5 mL / 100 mg x = (130 mg * 5 mL) / 100 mg x = 650 / 100 x = 6.5 mL The final sig will say: take 6.5 mL by mouth every day for 10 days Total quantity to be dispensed will be 6.5 mL * 10 days, which is 65mL But, Suprax comes in bottles of 50 mL, 75 mL and 100 mL So, the total quantity to be dispensed has to be 75 mL In this case, the pharmacist will have to dispense 1 bottle of 75mL The days supply is 10 days as stated by the doctor. Now, the pharmacist could re-write the directions: take 6.5 mL by mouth every day for 10 days. Discard the remainder.

What are the total quantity and the total days supply for the following Rx: Omnicef 125mg/5mL 1 3/4 tsp qd x6d ------------------------------------------------------------ The doctor has prescribed Omnicef 125mg/5mL oral suspension, but the pharmacist may very likely dispense the generic version Cefdinir 125mg/5mL oral suspension. The sig says: take 1 and 3/4 teaspoonsful by mouth every day for 6 days Notice that 3/4 = 0.75 Then, the patient will take 1 and 0.75 teaspoonsful daily for 6 days, that is, the patient will take 1.75 teaspoonsful daily for 6 days. Also, notice that 1 tsp = 5 mL So, the patient will take 1.75 * 5mL * 6 days which is 53mL But, the smallest size of Omnicef 125mg/5mL is a bottle of 60mL Therefore, the total quantity to be dispensed will be 60mL The total days supply is 6 days as stated by the doctor. Now, the pharmacist could re-write the directions: take 1 and 3/4 teaspoonsful by mouth every day for 6 days. Discard the remainder.

Calculate the total quantity and the total days supply for the following Rx: Zithromax 200mg/5cc disp: 5d 20cc am one time, then 10 cc qam x 4d ------------------------------------------------------------ The doctor has prescribed Zithromax 200mg/5mL oral suspension. But, most pharmacists will dispense the generic version Azithromycin 200mg/5mL oral suspension. The total days supply is 5 days as stated by the doctor. The sig says: take 20 mL by mouth in the morning one time only, then take 10 mL every morning for 4 days In this case, the patient has to take 20 mL on the first day. Then, the patient has to take 10 mL for 4 days, that is, the patient will take 40 mL So, the patient will take 40 mL + 20 mL which is 60 mL Therefore, the total quantity to be dispensed will be 60 mL But, the pharmacist will very likely dispense two bottles of 30 mL each.

What are the total quantity and the total days supply for the following Rx: Zithromax 200 30cc 2 po qd x 3d ------------------------------------------------------------ The doctor has prescribed the brand-name drug Zithromax 200mg/5mL oral suspension, but the pharmacist will very likely dispense the generic version Azithromycin 200mg/5mL oral suspension. The pharmacist will dispense a bottle of 30 cc, that is, 30 mL In turn, the total quantity to be dispensed is 30 mL as stated by the doctor. The sig says: take 2 teaspoonsful by mouth every day for 3 days Notice that 1 tsp = 5 mL and then 2 tsp = 10 mL The patient will take 10 mL every day for 3 days, that is, the patient will take a total of 30 mL The total days supply is 3 days as stated by the doctor. In fact, there is no need to calculate anything because the sig has clearly described the quantity and the days supply.

Calculate the total quantity and the total days supply for the following Rx: Zithromax 100mg/5mL 1 tsp po on day 1, then 1/2 tsp on days 2 thru 5 ------------------------------------------------------------ The doctor has prescribed the brand-name drug Zithromax 100mg/5mL oral suspension, but the pharmacist will very likely dispense the generic version Azithromycin 100mg/5mL oral suspension. This strength of azithromycin is usually prescribed for children. The sig says: give 5 mL by mouth on day 1, then give 2.5 mL on days 2 thru 5 The child will take 5 mL on day 1 and, then, the child will take 2.5 mL on days 2, 3, 4, and 5 In other words, the child will take 5 mL on day 1 and the child will take 10 mL during the next four days. So, the total quantity to be dispensed is 15 mL In this case, the pharmacist will dispense one bottle of 15 mL The total days supply is 5 days.

Calculate the total quantity and the total days supply for the following Rx: Zmax susp 100/5 2 and 1/2 tsp on day 1, then 1 and 1/4 tsp for 4 days ------------------------------------------------------------ The doctor has prescribed the brand-name drug Zithromax 100mg/5mL oral suspension, but the pharmacist will very likely dispense the generic version Azithromycin 100mg/5mL oral suspension. The sig says: take 2 and 1/2 teaspoonsful by mouth on day 1, then take 1 and 1/4 teaspoonsful on days 2, 3, 4, and 5 Notice that 2 + 1/2 is the same as 2 + 0.5 and, in turn, 2 + 0.5 = 2.5 Keep in mind that 1 teaspoon = 5 mL Now, the patient will take 2.5 teaspoon on day 1, that is, the patient will take 2.5 * 5mL on day 1 In other words, the patient will take 12.5 mL on day 1 Then, the patient will take 1 and 1/4 teaspoon for 4 days. Notice that 1 + 1/4 is the same as 1 + 0.25 and, in turn, 1 + 0.25 = 1.25 In turn, the patient will take 1.25 teaspoon for 4 days, that is, the patient will take 1.25 * 5mL * 4 days. In other words, the patient will take 25 mL in the next four days. So, the patient will take 12.5 mL on day 1 and then the patient will take 25mL in the next four days. In turn, the patient will take 12.5 + 25 = 37.5 Therefore, the patient will take a total of 37.5 mL But, Azithromycin 100mg/5mL oral suspension comes in bottles of 15 mL In this case, the pharmacist will have to dispense 3 bottles of 15 mL each. Then, the total quantity to be dispensed will be 45 mL Now, the total days supply is 5 days as implied by the sig directions.

What is the total quantity for the following Rx: Zmax 2 gm bottle suspension 1 dose po once ------------------------------------------------------------ The doctor has prescribed the brand-name drug Zmax 2gm oral suspenstion. This medicine is a 2-gram oral suspension and we need to add 60 mL of water into the bottle. The sig says: take the entire dose by mouth all at once In this case, the pharmacist will dispense the whole bottle. The total quantity to be dispensed is either 1 bottle or 60 mL depending on the pharmacy computer system.

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