Medical Office Pharmacology: Review For Medical Assistant Students and Professionals
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For medical assistants who need to brush up on certain areas in pharmacology as it applies to a medical office.
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The need for well trained medical assistants remains high. At any given moment there are over 100,000 job offers for medical assistants and other healthcare professionals available across the nation, hundreds in every state! Most disciplines require knowledge of medical office procedures and some pharmacology....
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Drug Dosage Calculations
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The following terms are used in connection with doses:
Therapeutic dose: Also referred to as the normal adult dose, the usual dose or average dose, it is the amount needed to produce the desired therapeutic effect. Dosage range: A term that applies to the range between the minimum amount of drug and the maximum amount of drug required to produce the desired effect. Minimum dose: The least amount of drug required to produce a therapeutic effect. Maximum dose: The largest amount of drug that can be given without reaching the toxic effect. Toxic dose: The least amount of drug that will produce symptoms of poisoning. Minimum lethal dose: The least amount of drug that can produce death. Consider the following:The amount of medication to be administered is referred to as the dose. The study of dosage and the criteria, which influence it is called posology.
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Calculation of A Dose:
MILLIGRAM
If you are trying to find out what a milligram actually might look like, take a raisin, cut it into 1000 equal parts. There--each little part will weigh about 1 milligram! There are 453,592.37 milligrams in a pound. The fact that most drugs are measured in milligrams should alert you to realize that sometimes the most miniscule amounts of a substance can be very powerful. Label instructions should be followed very carefully.
Often, in a medical office or clinic, the doctor orders a medication and requests that the patient receives the initial, or whole dose of the prescribed drug before leaving the office. Also, there are patients that come to the medical office for the sole purpose of receiving a dose of a prescribed medication, such as allergy shots, Vitamin B 12 injections, flu shots, without seeing the doctor that day.
Factors Affecting Drug Effect:
The two primary factors that determine or influence the dose are age and weight;
but wait, there are more!
AgeWeightGenderTime of administrationImmune responseToleranceAccumulationPathological factorsPsychological factorsOther factors:
Genetic make-up (nationality, race)OccupationHabitual useFrequency of administrationMode of administrationPROBLEM SOLVING:
Problem is, sometimes the dosage or medication's strength is not the same as the strength that you have on hand. In other words the doctor orders 500 mg of a certain medication in tablet form, you go to get the medication storage area and find it on the shelf, but when you check the label it is not the exact same strength as ordered. The only tablets you have on hand are 250 mg strength.
What to do next? The answer is rather simple, you must calculate the correct dose! In order to calculate the correct dose, you need to use the correct formula! The following formula to calculate dosage is easy to remember and if used properly it delivers the correct result in every instance:
_Desired dose_
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x quantity of on-hand dose = desired dose
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(That's: Desired dose divided by on-hand strength, multiplied by the quantity of on-hand dose (e.g.. 1 tablet), equals desired dose)
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On-hand strength
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For example, if a physician orders 500 mg of ibuprofen for a patient (which is the desired dose,) and you have 250 mg tablets (1 tablet = 250 mg) on-hand, the medical caregiver needs to dispense two tablets, because 500 divided by 250, then multiplied by 1 (one tablet) equals the desired dose, which comes to 2 (two tablets).
_500_
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x 1 (tablet) = 2 tablets
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(That's: 500 divided by 250, multiplied by 1 tablet, equals 2 tablets)
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250
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This formula works with any other type and strength of medication, whether tablets, suppository, or liquid (drops, suspensions, syrups etc.)
Had it been the other way around and the doctor had ordered 250 mg of ibuprofen but all you had on hand was 500 mg tablets, your calculation would look like this:
_250_
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x 1 (tablet) = 0.5 tablets
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(That's: 250 divided by 500, multiplied by 1 tablet, equals half of a tablet)
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500
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It even works for a liquid medication, for example where 1 cc (liquid) delivers 500 mg of a drug. If the doctor ordered 1500 mg of the drug you calculate:
_1500_
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x 1 cc = 3 cc
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(That's: 1500 divided by 500, multiplied by 1 cc, equals three cc liquid)
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500
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Remember: 1 cc is the exact same amount as 1 ml!
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To report illegal prescription drug sales and/or rogue pharmacies operating on the Internet call the anonymous Pharmaceutical Drug Abuse Hotline: 1-877-RxAbuse (1-877-792-2873).
More info at: DEA Website
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CONSUMER ALERT:
Buying drugs online may be illegal!
Federal law prohibits buying controlled substances such as narcotic pain relievers (e.g., OxyContin®, Vicodin ®), sedatives (e.g., Valium®, Xanax®, Ambien®), stimulants (e.g., phentermine, phendimetrazine, Adderall®, Ritalin®) and anabolic steroids (e.g., Winstrol®, Equipoise®) without a valid prescription from a doctor. This means there must be a bonafide doctor-patient relationship, which by most state laws requires a physical examination to receive a prescription. Prescriptions written by "cyber doctors" relying on online questionnaires are not legitimate under the law.
Buying controlled substances online without a valid prescription may be punishable by imprisonment under Federal law and it is a felony to import drugs into the United States and ship to a non-DEA registrant.
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About the Author:
Danni R. has created this extensive resource in her capacity as certified medical assistant and medical assisting instructor at Porter & Chester Institute, Ultrasound Diagnostic School, and Branford Hall in 2003. You may also visit her other websites at Advanced Medical Assistant of America, Medical Assistant Net, Medical Billing and Coding Net, Medical Coding and Billing Home Page, and Phlebotomy Pages to get better acquainted with her work.