Health Guide
Drug Guide

Valproic acid (Oral route, parenteral route)

Brand Names:

Dosage Forms:

Uses of This Medicine:

Valproic acid, valproate sodium, and divalproex belong to the group of medicines called anticonvulsants. They are used to control certain types of seizures in the treatment of epilepsy. Valproic acid, valproate sodium, and divalproex may be used alone or with other seizure medicine. Divalproex is also used to treat the manic phase of bipolar disorder (manic-depressive illness), and to help prevent migraine headaches.

Divalproex and valproate sodium form valproic acid in the body. Therefore, the following information applies to all of these medicines.

These medicines are available only with your doctor's prescription.

Before Using This Medicine:


Tell your doctor if you have ever had any unusual or allergic reaction to medicines in this group or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Abdominal or stomach cramps, nausea or vomiting, tiredness or weakness, and yellow eyes or skin may be especially likely to occur in children, who are usually more sensitive to the effects of these medicines. Children up to 2 years of age, those taking more than one medicine for seizure control, and children with certain other medical problems may be more likely to develop serious side effects.

Older adults

Elderly people are especially sensitive to the effects of these medicines. This may increase the chance of side effects during treatment. The dose of this medicine may be lower for older adults.


Valproic acid, valproate sodium, and divalproex have been reported to cause birth defects when taken by the mother during the first 3 months of pregnancy. Also, animal studies have shown that valproic acid, valproate sodium, and divalproex cause birth defects when taken in doses several times greater than doses used in humans. However, these medicines may be necessary to control seizures in some pregnant patients. Be sure you have discussed this with your doctor.


Valproic acid, valproate sodium, and divalproex pass into the breast milk, but their effect on the nursing baby is not known. It may be necessary for you to take another medicine or to stop breast-feeding during treatment with valproic acid, valproate sodium, or divalproex. Be sure you have discussed the risks and benefits of this medicine with your doctor.

Other medicines

Using medicines in this class with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Other interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems

The presence of other medical problems may affect the use of medicines in this class. Make sure you tell your doctor if you have any other medical problems, especially:

Proper Use of This Medicine:

For patients taking the capsule form of valproic acid:

For patients taking the delayed-release capsule form of divalproex:

For patients taking the delayed-release tablet form of divalproex:

For patients taking the syrup form of valproic acid:

For patients taking the oral dosage forms of valproic acid and divalproex:

This medicine must be taken exactly as directed by your doctor to prevent seizures and lessen the possibility of side effects.


The dose medicines in this class will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of these medicines. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed dose

Call your doctor or pharmacist for instructions.

If you miss a dose of this medicine, and your dosing schedule is:

If you have any questions about this, check with your doctor.


Keep out of the reach of children.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Do not keep outdated medicine or medicine no longer needed.

Precautions While Using This Medicine:

Your doctor should check your progress at regular visits, especially for the first few months that you take this medicine. This is necessary to allow dose adjustments and to reduce any unwanted effects.

Do not stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping completely.

Before you have any medical tests, tell the doctor in charge that you are taking this medicine. The results of the metyrapone and thyroid function tests may be affected by this medicine.

Before having any kind of surgery, dental treatment, or emergency treatment, tell the medical doctor or dentist in charge that you are taking this medicine. Valproic acid, valproate sodium, or divalproex may change the time it takes your blood to clot, which may increase the chance of bleeding. Also, taking valproic acid, valproate sodium, or divalproex together with medicines that are used during surgery or dental or emergency treatments may increase the CNS depressant effects.

Valproic acid, valproate sodium, and divalproex will add to the effects of alcohol and other CNS depressants (medicines that make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are using this medicine.

For diabetic patients:

Your doctor may want you to carry a medical identification card or bracelet stating that you are taking this medicine.

This medicine may cause some people to become drowsy or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are drowsy or not alert.

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

More common
Body aches or pain
dryness or soreness of throat
runny nose
tender, swollen glands in neck
trouble in swallowing
voice changes
Less common
Abdominal or stomach cramps (severe)
behavioral, mood, or mental changes
blurred vision
continuous, uncontrolled back-and-forth and/or rolling eye movements
double vision
faintness, or light-headedness when getting up from a lying or sitting position suddenly
fast, irregular, pounding, or racing heartbeat or pulse
heavy, nonmenstrual vaginal bleeding
increase in seizures
loss of appetite
nausea or vomiting (continuing)
rapid weight gain
redness or swelling in ear
spots before eyes
swelling of face, arms, hands, lower legs, or feet
tingling of hands or feet
tiredness and weakness
unusual bleeding or bruising
unusual tiredness or weakness
unusual weight gain or loss
vomiting of blood or material that looks like coffee ground
yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
Abdominal or stomach cramps (mild)
acid or sour stomach
change in menstrual periods
hair loss
lack or loss of strength
loss of appetite
loss of bowel control
mental depression
nausea and vomiting
quick to react or overreact emotionally;
rapidly changing moods
sleepiness or unusual drowsiness
stomach discomfort, upset or pain
trembling of hands and arms
weight loss or gain
Less common or rare
Absence of or decrease in body movement
absent, missed, or irregular menstrual periods
anxiety; nervousness; restlessness
bloated full feeling
bloody or cloudy urine
bloody nose
burning, crawling, itching, numbness, prickling, "pins and needles" , or tingling feelings
burning, dry or itching eyes
change in taste
clumsiness or unsteadiness
coin-shaped lesions on skin
cold sweats
decreased awareness or responsiveness
degenerative disease of the joint
difficult, burning, or painful urination
difficulty in moving
difficult or labored breathing
discharge; excessive tearing of eye
dry mouth
excess air or gas in stomach or intestines
excessive muscle tone; muscle tension or tightness
feeling of constant movement of self or surroundings
feeling sad or empty
feeling of warmth or heat
flushing or redness of skin, especially on face and neck
frequent urge to urinate
heavy bleeding
irregular heartbeats
joint pain; swollen joints
lack of appetite
lip smacking ; uncontrolled chewing movements
loss of hair
loss of interest or pleasure
loss of memory
problems with memory
mimicry of speech or movements
muscle aching or cramping
muscle pains or stiffness
normal menstrual bleeding occurring earlier, possibly lasting longer than expected
passing gas
peculiar postures or movements, mannerisms or grimacing
puffing of cheeks
rapid or worm-like movements of tongue
redness, pain, swelling of eye, eyelid, or inner lining of eyelid
redness, swelling, or soreness of tongue
runny nose
seeing, hearing, or feeling things that are not there
sensation of spinning
severe sleepiness
shortness of breath
skin rash
small red or purple spots on skin
stopping of menstrual bleeding
stuffy nose
tightness in chest
trouble concentrating
trouble in speaking
slurred speech
trouble sleeping
uncontrolled chewing movements
uncontrolled movements of arms and legs
unusual excitement, restlessness, or irritability

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Last Updated: 6/12/2013

Thomson Micromedex. All rights reserved.

Thomson & A.D.A.M