Hello and welcome to Introduction to Pharmacology. My name is Dr. Bill Deal-Jones. I'm a professor in the Faculty of Health Disciplines at Athabasca University.
In this video, we'll be talking about drug nomenclature. It's important to remember that all drugs have three names, the chemical name, the generic or non-proprietary name, and the trade or brand name. For example, we can speak about the same drug in this case. and start by using its chemical name, 2-acetyloxybenzoic acid.
The generic or non-proprietary name would be acetyl salicylic acid. Sometimes that's abbreviated as ASA. The trade or brand name, which is the name given by the pharmaceutical company under which the drug is marketed, could be Bayer aspirin or antrophin. And note that in both cases here, there's a small R at the end of each of these, indicating that it's a registered drug trademark to that particular company.
Beyond knowing whether we're speaking about the chemical, generic, or trade names of a drug, it's important to appreciate that there are different types of drug formulations and that we need to be as specific as possible. For example, iron supplements can be referred to in their generic names as either ferrous gluconate, ferrous fumarate, ferrous sulfate, and so on. And each of these are different formulations, which may have different tolerances and maybe have different dosages and different bioavailabilities.
So it's important to specify this. particular formulation when referring to a drug. As well, there are drug acronyms which may come after the drug name.
In this case, we can talk about diltiazem, which is a calcium channel blocker, and it can be written as diltiazem, diltiazem CD, or diltiazem ER. Diltiazem CD refers to controlled delivery, and in this case, the formulation is based on core small bead of sugar that's coated with diltiazem and then layered with a rate-controlling polymer. This results in two peaks in drug release over 24 hours. Diltiazem ER refers to extended release, and this formulation is based on a paste that converts to beads coated with rate-controlling polymer, and that results in a more uniform release of the drug over 24 hours.
Other acronyms in this category include CR for controlled release, LA for long-acting, SR for sustained release, TR for timed release, XL for extended release. Oxycodone, which is an opioid pain reliever, is written in both its generic form here, oxycodone, lowercase at the beginning, versus antioxicontin, which is one of the possible trade names. There are other trade names for oxycodone, such as Percodan. And this brings up a good question.
When prescribing drugs, should prescribers write the script using the generic or the trade name? And most prescribers will agree that it's best to use the generic name where possible. And there's a couple of reasons for that. One, of course, is the avoidance of any...
bias for a particular brand, and also it can reduce confusion. Here are some other examples of potential naming errors. You'll see oxycodone, 20 milligrams PO, or per os, or by mouth, Q12H, can be written if the prescriber wants to use a specific trade name as oxycontin, 20 milligrams PO, Q12H.
There are some other issues which may arise. For example, ranitidine, which is a histamine receptor blocker, can be written as ranitidine, 125 milligrams, POBID, or twice daily. However, if one is referring to it by its brand name, one of its brand names, which is Zantac, then there's a slightly different dosage. Zantac, 150 milligrams, POBID.
And I'll leave it to you to look at the other examples, such as calcium. and Cytoksan and see if you can spot the differences between the two ways of naming. And the preferred naming is indicated with a small check.
Another good reason for using the generic name in drug prescriptions is that there can be problems with trade names. For example, if one is unaware of all the different trade names of the drug, patients may receive duplicate orders. For example, lisinopril, which is an ACE inhibitor, is marketed as either Prinvil or Zestrel. So a patient could be receiving two different drugs, which in fact are the same medication. There can also be confusion between drugs which have sound-alike names.
For example, Celebrex, which is cyclooxygenase inhibitor, or NSAID. and is used for arthritis or rheumatoid arthritis, may be confused with Celexa, which is a benzodiazepine, which is the same as citalopram. So again, this highlights the benefits of using the generic and non-trade name.
The issue of generic versus trade names is further highlighted by the fact that different countries may use different trade names. For example, omeprazole can be marketed as either Losec or Prilosec. The fetipine is either Adalat or Procardia.
And moreover, some trade names are applied to combination products, that is, drug formulations in which there is more than one drug. An example of this is diazide, which is a trade name for a medication that includes both hydrochlorazine thiazide, and triamterine. Of course, when in doubt, we can always go to validated drug information resources, and I've listed a few here.
Compendium of Pharmaceuticals and Specialties, or the CPS, also known as the Blue Book, is a great resource. It has white, purple, and green pages which contain drug monographs, clinical information, and generic and brand name indices, respectively. Rxtx which I really like because it's Canadian content, it's updated continuously, and it's really an authoritative source for prescribing and managing drug therapy at the point of care.
It comes as an e-text, and if one is looking for specific information on anti-infectives, the Anti-Infective Guidelines for Community-Acquired Infections is a great resource. It's Canadian content, it's updated annually, and available as either paper and e-text, and Merck Manual. Now, there are many people who fall to the temptation of using resources such as Wikipedia or Drugs Online or WebMD.
And these are not validated sources for drug information. They're not always updated, and they may not refer to the Canadian context. And there's no real good guarantee that they have solid information, mechanisms of action.
or drug dosages. So you're best to always use a respected drug resource. Thanks very much and that's the end of this video.