Meds and you

Updated 05 July 2013

A glossary of drug label terms

Don't know a side effect from an adverse effect? Can't tell a precaution from a warning? You're not alone.


Don't know a side effect from an adverse effect? Can't tell a precaution from a warning? You're not alone.

While experts advise talking to your doctor or your pharmacist about any aspect of your medication -- or the instructions -- that aren't clear, the following glossary of terms can help you use all medications more safely and effectively.

Side Effects
What it means: These were the accepted, sometimes expected reactions documented in a significant number of people while the drug underwent clinical testing. Though the list can seem daunting, the effects are cited in descending order, from the most common to the most rare, with those mentioned first far more likely to occur than those listed last.
The bottom line: Most side effects are categorized according to frequency, which is defined as follows: common - one in 10,000; uncommon - one in 100,000; rare - one in 1,000,000.

Adverse Events
What it means: This describes an effect noted during clinical trials of a drug and may or not may be related to drug use. Adverse events are listed because manufacturers are required by law to report virtually all major effects observed during clinical trials - whether they can be linked to the drug or not. Because many factors can help determine an adverse event - including a person's age, sex, genetics and any co-existing health problems - most don't apply to the general population.
The bottom line: Experts say the chance of experiencing an adverse event is extremely rare.

What it means: These are the conditions under which a drug should not be used - either because it has been found unsafe in certain situations, or because information is limited and safety concerns are suspected. Common contraindications include pregnancy, breast feeding, or regular use of certain other medications.
The bottom line: Pay attention to this box and always bring to your doctor's attention any contraindication that you believe may apply to you - particularly interactions with other medications you may be taking from a different physician.

What it means: This advises you of any special steps needed to safely and effectively use the medication. It can also be a "catch all" for general warnings that don't fit into other categories - including pediatric use or potential drug interactions. Although the information in this section can be useful, it is rarely based on strong scientific data. It is usually gleaned from anecdotal reports or patient volunteer findings.
The bottom line: Precautions generally are limited to problems that are rarely seen or not seen at all in human studies. Don't ignore precautions, but don't worry unless they specifically apply to you.

What it means: Under this heading you will find serious adverse reactions or events and potential safety hazards of a drug, and sometimes information about potential serious allergic reactions. In general, the possibilities listed in this section are rare. Data considered particularly hazardous - such as risk of death or serious organ damage - is usually outlined in a "black box." Unless the information highlighted in the box describes you or your specific condition, the drug is most likely safe for you.
The bottom line: Bring to your doctor's attention any conditions within the warning section that specifically apply to you.

Clinical Pharmacology
What it means: This describes how a drug works in the body and is important only when it interferes with a medical concern. For example, if a drug works by speeding up the heart rate, and you have a weak heart, then the drug's clinical pharmacology might not be right for you.
The bottom line: The information here helps your doctor in choosing the right drug for you, and it underscores the need to make certain that every doctor who prescribes a drug for you is aware of your full health history and every other drug you are taking.

Indications and Usage
What it means: This indicates the specific conditions for which the drug has been tested and approved. However, be aware that many drugs are used in what is called "off label" prescribing - to treat conditions other than what the medicine was originally approved for.
The bottom line: If your ailment isn't on the list, ask your doctor if this drug is being prescribed "off label" and ask why.

Dosage and Administration
What it means: This section highlights recommended dosage, range of available strengths and forms, (example: 5mg, 10mg, 15 mg tablets), maximum and minimum dosages and frequency of use - all things that can change in accordance with what ailment the drug is being prescribed for.
The bottom line: Always take a drug exactly as your doctor prescribes, but do bring any discrepancies in dosing you find in this section to the attention of both your doctor and pharmacist. Also, be certain to read the dosing and frequency instructions printed on the label of the prescription bottle itself (telling you how much to take and how often to take it), and read them every time a drug is re-filled, or if it is prescribed again after months of non-use.

(Health24, updated January 2009)


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