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Buphenyl Side Effects

Generic Name: sodium phenylbutyrate

Note: This document contains side effect information about sodium phenylbutyrate. Some of the dosage forms listed on this page may not apply to the brand name Buphenyl.

For the Consumer

Applies to sodium phenylbutyrate: oral powder, oral tablet, oral tablet enteric coated

Along with its needed effects, sodium phenylbutyrate (the active ingredient contained in Buphenyl) 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 immediately if any of the following side effects occur while taking sodium phenylbutyrate:

More common
  • Change in the frequency of breathing
  • lack of or irregular menstruation
  • lower back, side, or stomach pain
  • mood or mental changes
  • muscle pain or twitching
  • nausea or vomiting
  • nervousness or restlessness
  • swelling of the feet or lower legs
  • unpleasant taste
  • unusual tiredness or weakness
Less common Rare
  • Convulsions (seizures)
  • dizziness
  • dryness of the mouth
  • fast, slow, or irregular heartbeat
  • increased blood pressure
  • increased thirst
  • irritability
  • muscle cramps
  • rectal bleeding
  • swelling of the face
  • unusual weight gain
  • weak pulse

Some side effects of sodium phenylbutyrate 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:

Less common
  • Changes in taste
  • decreased appetite
  • strong body odor
Rare

For Healthcare Professionals

Applies to sodium phenylbutyrate: oral powder for reconstitution, oral tablet

General

Causality of adverse effects is sometimes difficult to determine because they may result from either the underlying disease, the patient's restricted diet, intercurrent illness, or the drug itself.[Ref]

Endocrine

Very common (10% or more): Amenorrhea/menstrual dysfunction (23%)[Ref]

Metabolic

Very common (10% or more): Acidosis (14%), hypoalbuminemia (11%)
Common (1% to 10%): Alkalosis, decreased appetite, hyperchloremia, hypophosphatemia, decreased total protein, hyperuricemia, hyperphosphatemia, hypernatremia, hypokalemia, increased weight[Ref]

Cardiovascular

Common (1% to 10%): Edema
Uncommon (0.1% to 1%): Arrhythmia[Ref]

Dermatologic

Common (1% to 10%): Rash, body odor[Ref]

Gastrointestinal

Common (1% to 10%): Abdominal pain, nausea, vomiting, constipation, dysgeusia
Uncommon (0.1% to 1%): Pancreatitis, rectal bleeding/hemorrhage, peptic ulcer, gastritis[Ref]

Hematologic

Common (1% to 10%): Anemia, leukopenia, leukocytosis, thrombocytopenia, thrombocytosis
Uncommon (0.1% to 1%): Aplastic anemia, ecchymosis[Ref]

Hepatic

Common (1% to 10%): Increased alkaline phosphatase, increased liver transaminases, hyperbilirubinemia[Ref]

Nervous system

Common (1% to 10%): Syncope, headache, bad taste/taste aversion
Frequency not reported: Somnolence, fatigue, lightheadedness, hypoacusis, disorientation, impaired memory, exacerbation of preexisting neuropathy[Ref]

Psychiatric

Common (1% to 10%): Depression, irritability[Ref]

Renal

Common (1% to 10%): Renal tubular acidosis[Ref]

References

1. "Product Information. Buphenyl (sodium phenylbutyrate)." Horizon Pharma USA Inc, Northbrook, IL.

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer

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