Drug information of Carglumic acid

Carglumic acid

Drug group:

Carglumic acid is a man-made form of an enzyme that occurs naturally in the liver. This enzyme is necessary for processing excess nitrogen produced when the body metabolizes proteins. Without this enzyme, nitrogen builds up in the form of ammonia and is not removed from the body. Ammonia is very toxic when it circulates in blood and tissues and can cause permanent brain damage, coma, or death.

Carglumic acid is used to treat hyperammonemia (HYE-per-AM-moe-NEE-mee-a), a urea cycle disorder caused by lack of a certain liver enzyme. Carglumic acid is usually given with other medications to treat this lifelong disorder.

Mechanism of effect

N-acetylglutamate synthase (NAGS) is a mitochondrial enzyme which produces N-acetylglutamate (NAG). NAG is a required allosteric activator of the hepatic mitochondrial enzyme, carbamoyl phosphate synthetase 1 (CPS 1), which converts ammonia into urea in the first step of the urea cycle. In NAGS-deficient patients, carglumic acid serves as a replacement for NAG.



Via intestinal flora to carbon dioxide.


Feces (≤60% as unchanged drug); urine (9% as unchanged drug).

Time to Peak

Median: 3 hours (range: 2 to 4 hours).

Half-Life Elimination

25 hours.

Drug indications

Hyperammonemia: Adjunctive treatment of acute hyperammonemia and maintenance therapy of chronic hyperammonemia due to the deficiency of the hepatic enzyme N-acetylglutamate synthase (NAGS) in adult and pediatric patients


Usual Adult Dose for Hyperammonemia

Initial dose: 100 to 250 mg/kg/day orally divided into 2 to 4 doses (rounded to the nearest 100 mg)
Maintenance dose: 10 to 100 mg/kg/day orally divided into 2 to 4 doses (rounded to the nearest 100 mg)

Therapeutic monitoring: Plasma ammonia levels should be closely monitored; titrate dose to maintain plasma ammonia levels within the normal range

Usual Pediatric Dose for Hyperammonemia

Initial dose: 100 to 250 mg/kg/day orally divided into 2 to 4 doses (rounded to the nearest 100 mg)
Maintenance dose: 10 to 100 mg/kg/day orally divided into 2 to 4 doses (rounded to the nearest 100 mg)

Drug contraindications

There are no contraindications listed in the manufacturer’s labeling.

Canadian labeling: Additional contraindications (not in US labeling): Hypersensitivity to carglumic acid or any component of the formulation; breastfeeding

Side effects

Side effects requiring immediate medical attention

Along with its needed effects, carglumic acid 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 carglumic acid:

More common

  • Chills
  • cough
  • decreased weight
  • diarrhea
  • fever
  • general feeling of discomfort or illness
  • headache
  • hoarseness
  • increased sweating
  • joint pain
  • loss of appetite
  • lower back or side pain
  • muscle aches and pains
  • nausea
  • painful or difficult urination
  • pale skin
  • runny nose
  • shivering
  • sore throat
  • sweating
  • trouble sleeping
  • troubled breathing with exertion
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vomiting

Get emergency help immediately if any of the following symptoms of overdose occur while taking carglumic acid:

Symptoms of overdose

  • Fast, pounding, or irregular heartbeator pulse
  • increase in mucous from the lungs
  • restlessness

Side effects not requiring immediate medical attention

Some side effects of carglumic acid 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

  • Change in hearing
  • change in taste
  • congestion
  • ear drainage
  • earache or pain in the ear
  • lack or loss of strength
  • loss of taste
  • rash
  • sleepiness or unusual drowsiness
  • stomach pain
  • stuffy or runny nose
  • swollen glands


Before taking this medicineTell your doctor about all of your medical conditions.
  • Carglumic acid is only part of a complete program of treatment that may also include a special diet and other medications. Follow all instructions of your doctor or dietitian. Learn about the foods to eat or avoid to help control your condition.
  • Follow your doctor's instructions about taking carglumic acid if you are pregnant. It is very important to control your ammonia levels during pregnancy. Do not stop taking carglumic acid without your doctor's advice, and tell your doctor right away if you become pregnant.
  • You should not breast-feed while you are using carglumic acid. Talk with your doctor about other medications that can be more safely used to control your ammonia levels while you are nursing a baby.
  • Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.
  • Carglumic acid is usually taken 2 to 4 times each day, just before each meal or feeding. Follow your doctor's instructions.
  • Carglumic acid doses are based on weight (especially in children and teenagers). Your dose needs may change if you gain or lose weight. Dose adjustments are especially important in children who are growing.
  • Do not crush or swallow the dispersible tablet Place it into a glass of water and allow the tablet to disperse (it will not dissolve completely). Drink this mixture right away. Add a little more water to the glass, swirl gently and drink right away.
  • The dispersed tablet may also be taken with an oral syringe or through a nasogastric (NG) feeding tube. Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you do not understand these instructions.
  • Your blood will need to be tested often. A buildup of ammonia in the blood can quickly cause brain injury or death.Even if you have no symptoms, tests can help your doctor determine if this medicine is effective. Every person with a urea cycle disorder should remain under the care of a doctor.
  • Store unopenedbottles of carglumic acid tablets in the refrigerator, do not freeze.
  • After opening the bottle, store at room temperature away from moisture and heat. Do not store opened bottles in the refrigerator.Keep the bottle tightly closed when not in use.
  • When you open the bottle, write the date on the bottle. Throw away any unused tablets 1 month (30 days) after the date of opening, or if the expiration dateprinted on the label has passed.

Pregnancy level


Use is acceptable

AU TGA pregnancy category: B1
US FDA pregnancy category: C

Comments: Women with N-acetylglutamate synthase (NAGS) deficiency must remain on this drug throughout pregnancy as untreated NAGS results in irreversible neurologic damage and death.

Breast feeding warning

Not recommended

Excreted into human milk: Unknown
Excreted into animal milk: Yes

Comments: An increase in mortality and impairment of body weight gain has been observed in neonatal rats nursed by mothers receiving this drug.

Drug forms


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