How to Read a Package Insert


When you fill a prescription at the pharmacy, you usually are given a brief summary of information about the drug. You may also get more detailed information, called a "package insert". The information in the package insert has been approved by the U.S. Food and Drug Administration (FDA) based on research (clinical trials) in which the medication is given to patients. Package inserts are available for all prescription medications approved by the FDA. Similar information is available for nonprescription medicines and for some herbal medicines and dietary supplements.

Package inserts can be found in a reference book called the Physicians' Desk Reference, better known as "the PDR." This book can be found in libraries on online. Package inserts can also be found on websites for companies that make prescription medications. 

Important Safety Information:

This section will highlight in a box any specific safety information about the drug. The information is described in more details farther down in the prescribing information.

Indications and Usage:

This section lists the uses (indications) for which the FDA has approved the drug.  The conditions that are named, or in this case the types of epilepsy, are those for which adequate research studies were performed before the medication was approved.

If your type of epilepsy is not listed, don't be alarmed. It is very common (and legal) for doctors, or other prescribers (i.e. health care professionals who can prescribe medications), to use medicines for types of epilepsy or other reasons that have not been listed in this section by the FDA. This is called “off-label” use of a medicine. This often occurs for less common types of epilepsy or seizures or for use of a medicine in children. It may be harder or more costly to do those studies before the FDA approves the drug for other uses. When using a medication “off-label”, the prescriber will review other studies, experiences with other patients, and the opinions of experts in the field. The medicine is then prescribed based on his or her professional judgment about whether it is likely to help you.

Keep in mind that some insurance companies may not provide prescription coverage and pay for a medicine that is prescribed “off-label”. Or they may provide partial coverage which means you may have to pay more to get the medicine.

Some seizure medicines are also used for conditions other than epilepsy. For example, some medicines may also be used for pain, migraine headaches, mood disorders or other problems. So if you need treatment for some other condition besides epilepsy, your doctor may consider whether the same medication could help with both things.

Dosage and Administration:

This section gives the recommended dosages of the medicine. Usually it will suggest how to start the drug (how much to give at first), then how to increase the medicine to an effective dose. Many times your doctor will suggest that you start the medicine at a lower dose than given here and increase the dosage more slowly to lessen the chance of side effects.

If the medicine is indicated for more than one use, you may see separate sections for each use. Separate information also may be given about how to give the medicine to children, older people, or those with certain medical problems.

If your doctor has prescribed a regimen that is very different from what you see in this section, ask why it’s different. Factors specific to you, such as other health problems or medications may mean that you need a different dose or need to take it differently than usual. Continue to follow your doctor’s plan and let him or her know how you are feeling on the medicine.

Dosage Strength and Forms:

This section lists what form the medicine comes in and the dosage in each tablet, capsule or liquid.


Contraindications are situations in which the medicine should not be used. For instance, a medicine should not be prescribed for someone who has had an allergic reaction to the same medication or one that's similar, or for someone who is taking another medicine that interacts with it in a harmful way.

This section also may warn doctors not to prescribe the medicine for people with certain medical conditions if they are at greater risk of dangerous side effects. For example, the package insert for Depakote warns that it should not be used by people with liver disease. It’s important to check this section if you have other medical disorders. However, always go over this information with your own doctor.

Warnings and Precautions:

This section discusses serious side effects that may occur in people who take this medicine. If especially severe or life-threatening problems have been mentioned in a box warning, more details will be given here. Pay attention to these warnings so you will recognize any symptoms that could suggest a serious problem. Yet, don’t get overly alarmed. Talk to your doctor first about how this information relates to you and what you should look for.

Precautions include information about how to use the medication most safely and effectively. It alerts the doctor about types of patients who need close observation.  Guidelines about any laboratory tests that should be performed before or during the time the medicine is being used will be given here. This section may list activities (such as driving) that require special caution while the medicine is being used. Sometimes the information on pregnancy appears in this section too.

This section also might warn that you shouldn't take this medicine with a particular food or other product (such as an antacid). It's a good idea to review this section to see if it lists any medicines, foods, or other products that you use regularly.

Adverse Reactions:

This section lists all the side effects that were reported in people who took this medicine while it was being tested. These effects are usually grouped by the body system affected and perhaps also by how many people reported each one.

Side effects listed as ‘frequent’ or ‘common’ may have happened only in small numbers of people who took the drug during studies. The package inserts compares the frequency of side effects in relation to those who took a placebo or inactive drug and those who took the active drug. They will also report on how often a side effect has been reported in any type of study or after it has been marketed.

These lists of "adverse events" can look scary because they include so many problems, ranging from minor to life-threatening. The thing to remember is that this section lists everything that happened to or was reported by people taking the medicine, regardless of whether it had any connection to the medicine.

You may experience some of the side effects on the list or none at all. Even the effects listed as being most frequent do not affect everyone who takes the medicine. Also keep in mind that often seizure medicines are tested in people who are also taking other seizure medicines. If you are taking a different seizure medicine, the effects may be different for you.

Some of these side effects are rare or infrequent and are not likely to be a problem for you. Yet if they are also talked about under Warnings or Precautions, go over these with your doctor.

Drug Interactions

One of the most important parts of the insert is the list of Drug Interactions—the effects that a medicine may have on other prescription or over-the-counter medicines. These other medicines could affect the seizure medicine or the seizure medicine could cause problems with your non-seizure medicines. If you are taking any of the medicines in this list, review all your medicines with your doctor and pharmacist.

Use in Specific Populations

Included in this section is a discussion of possible problems if the medication is taken during pregnancy or with breastfeeding. These are worth reviewing with your doctor if you are considering pregnancy. He or she may also have more information about the medicines from results of Pregnancy Registries of seizure medications. It’s important to remember that most women have healthy babies regardless of which medicine they use.

This section will also talk about the use of the medication in children, older people, and people with specific health problems that could affect the use of the medication.

Drug Abuse and Dependence

This section tells whether this medicine could be abused or cause psychological or physical dependence. The package inserts for most seizure medicines say that there is no evidence of abuse potential or dependence, or that it has not been tested in humans. Seizure medicines that are in the barbiturate or benzodiazepine groups (such as phenobarbital, Mysoline (primidone), and Klonopin (clonazepam)) can cause dependence, however.

If you have a history of dependence on drugs you may want to check this section to see whether this medicine could cause a problem for you. If you’ve been taking a medicine that can cause dependency, remember never to stop it quickly. The dose should be lowered very slowly under the advice of a doctor.


This section tells what the results of a large overdose of the medicine are likely to be and how they should be treated. This kind of information is mainly useful to medical personnel. If you suspect an overdose of medication, you should contact a poison control center or emergency room right away.


This section gives the chemical name of the drug and a diagram showing the various atoms and molecules in the drug. It tells what form it comes in, for example tablets, capsules or liquid and what dosages are available. It also lists all inactive ingredients such as fillers, artificial colors, or flavorings. If you have food sensitivities, you can check to see what other substances are used to make this medicine.

Clinical Pharmacology:

A lot of the information in this section may be hard to understand. You'll see words like "Pharmacodynamics," "Pharmacokinetics" and "Bioavailability." Basically, this section tells how the medicine works in the body, for example how it is absorbed, eliminated, and how it works at different amounts. This section will also describe if there are differences in how it works for different groups of people, for example children, elderly people, women, or people of different races. If you have a special problem like kidney or liver disease, this is one of the sections your doctor will look at while deciding whether to prescribe this type of medicine for you, and if so, how much to give and when.

Nonclinical Toxicology:

This section summarizes studies of the medication in animals that is important to how it may be used in humans. It may have information about potential problems that can’t be studied in humans. For example whether or not a medicine could lead to cancer, fertility problems or other health problems. This type of information can not be obtained from testing for short periods in people.

Clinical Studies:

This section describes results of the clinical studies that show how effective or helpful the drug is and what risks or side effects may occur. The details in this section can help doctors understand how the drug works when it’s compared to a placebo or inactive drug, how it works when it’s given alone, or how it works when given with other seizure medications.

How Supplied, Storage and Handling:

This section lists all the available forms of this medicine, including tablets or capsules of various doses and perhaps liquids. Each one is described by color, shape, and markings, so you can be sure of which one you are taking. If you have a liquid, is it a suspension that needs to be shaken before use?

This section also gives storage instructions. This is where you find out whether to keep the liquid form in the refrigerator or not. It also tells whether pills should be kept away from heat, light, or moisture. Usually there's a recommendation against exposing the medicine to temperatures over 30ºC (86ºF), for instance, so if you pick up your prescription from the pharmacy on a hot day, don't leave it in the car while you run other errands!

Patient Counseling Information

This section is written in an easier to understand way and gives important information from the package insert about how to use the drug, side effects, warnings and precautions. These are reminders of important information that prescribers should tell patients about the drug. It does not cover all information that you may need to know. There is also a Medication Guide produced by the manufacturer of the drug that may give more guidance to patients taking the medicine.

Authored By:

Joseph I. Sirven MD / Patricia O. Shafer RN, MN
Steven C. Schachter, MD

on Friday, August 02, 2013

Reviewed By:

Joseph I. Sirven MD / Patricia O. Shafer RN MN

on Wednesday, March 19, 2014


Epilepsy Centers

Epilepsy centers provide you with a team of specialists to help you diagnose your epilepsy and explore treatment options.


Epilepsy Medication

Find in-depth information on anti-seizure medications so you know what to ask your doctor.


Epilepsy and Seizures 24/7 Helpline

Call our Epilepsy and Seizures 24/7 Helpline and talk with an epilepsy information specialist or submit a question online.


Tools & Resources

Get information, tips, and more to help you manage your epilepsy.