(sodium phenylbutyrate) Tablets
(sodium phenylbutyrate) Powder
What is the most important information I should know
BUPHENYL is prescribed along with changes in diet for
long-term treatment of urea cycle disorders. BUPHENYL can only be obtained with
a prescription from your doctor.
BUPHENYL must be taken exactly as the doctor prescribes;
do not increase or decrease the dose of this medication without the doctor's
What are urea cycle disorders ?
Urea cycle disorders include a group of diseases, each
having a specific liver enzyme deficiency. Because they are inherited, other
family members may be affected. These disorders vary in severity and may be
first detected at various ages, from newborn infants to adults. They lead to
increased amounts of ammonia in the blood, which may cause disturbed brain
function and severe brain damage. Typical signs of the disease are decreased
mental awareness, vomiting, combativeness, slurred speech, unstable
gait, and unconsciousness. The diagnosis of urea cycle disorders requires
special laboratory tests. These typical signs of the disease may recur after
the diagnosis is made if the condition is not under control. If they do,
the doctor should be notified immediately because this is a medical emergency.
An infection can cause the condition to go out of control. Therefore, if a fever
develops, the doctor should be seen immediately.
A patient or carrier of these disorders should wear a
Medic Alert tag stating the diagnosis. In the event that the patient has a sudden,
rapid accumulation of ammonia in the blood, and, therefore, in the brain,
leading to unconsciousness, the doctor will be alerted to treat the disease
Periodically, depending upon the severity of a particular
patient's urea cycle disorder, it will be necessary to perform blood tests.
These include plasma ammonia, plasma amino acid levels, and other more routine
blood tests to evaluate nutritional status.
What is BUPHENYL?
BUPHENYL is a drug that helps to prevent ammonia from
accumulating in the blood. BUPHENYL aids the body in eliminating substances
that produce ammonia. However, despite drug treatment, blood ammonia levels may
become elevated periodically and there may be episodes of altered brain
function in association with these ammonia elevations. Patients who have
disease onset as newborns have a high incidence of mental retardation. Medical
attention should be obtained as soon as signs appear (see above under
“What are urea cycle disorders?”). BUPHENYL may be used as life-long
therapy or as a temporary measure until liver transplantation is performed.
What diet should I or my child follow?
In addition to taking BUPHENYL, it is equally important
that a prescribed diet be followed. Because there is great variability in the
severity of urea cycle disorders, each patient's diet should be custom designed
by a physician and a nutritionist. Because the diet is so important, it is
recommended that the prescribed diet be discussed with a nutritionist who is
familiar with urea cycle disorders.
Who should not take BUPHENYL?
BUPHENYL is prescribed only for patients with urea cycle
disorders. It is not to be used for any other reason. Keep the medication in a
safe place where children cannot reach it.
What other medical conditions may also be present that
could increase the risk of taking BUPHENYL?
Heart failure or decreased kidney function may lead to
retention of the sodium content of BUPHENYL with potentially serious
consequences such as worsening heart failure, high blood pressure, and swelling.
If these medical conditions are present, the doctor will determine if your
child should take BUPHENYL.
How should I or my child take BUPHENYL?
The dose of BUPHENYL prescribed for adults and children
is based upon the patient's weight or size. It is very important that the full
amount prescribed for any 24-hour period be taken. If a dose is missed it should
be administered as soon as possible that same day. The total daily dose should
be administered in equally divided amounts with meals.
What medications should I or my child avoid or be cautious
of taking while on BUPHENYL?
Patients with urea cycle disorders usually should not
take Depakene (valproic acid), a drug sometimes prescribed for seizure
disorders, or Haldol (haloperidol), a drug used to treat certain types of psychiatric
or neurologic disorders. Both of these drugs have been reported to increase
blood ammonia levels. Steroids may break down body protein, thereby increasing
blood ammonia levels. The doctor should be consulted before administering
medications containing steroids.
What medications may affect the way the body breaks
down the drug?
Probenecid, a medication used to treat gout, may affect
the way the kidneys excrete BUPHENYL (consult the doctor for details).
What are the most common side effects of BUPHENYL?
The most common side effect reported in premenopausal
women taking BUPHENYL was absent or irregular menstrual periods. Decreased
appetite was reported in 4% of all people treated. Body odor and bad taste were
each reported in 3% of all patients treated.
A breakdown product of BUPHENYL has been associated
mainly with sleepiness and light-headedness. Because these symptoms may also be
due to the urea cycle going out of control, a doctor should see the patient
immediately if these symptoms occur, so the cause can be determined. Blood
tests should be performed periodically for adverse effects and for levels of
medication and its breakdown products.
How should BUPHENYL be stored?
BUPHENYL should be stored in a tightly closed bottle at
This leaflet provides a brief summary of the information
available on BUPHENYL. The information here is incomplete and is not designed
to take the place of your doctor's instructions. For more complete information,
consult your physician, or contact Horizon Therapeutics, Inc. at 1-855-UCD-SUPT