Cysteine (Intravenous)

Cysteine injection is used to fulfill the nutritional needs of newborn infants (including preterm babies) who need total parenteral nutrition (TPN).

Cysteine injection is also given to adults and children with severe liver disease who may have problems with their enzyme functions and need TPN. This medicine may also be used to offer a more complete range of amino acids for protein synthesis.

This medicine is to be given only by or under the direct supervision of your doctor.

Your doctor will monitor you or your child's progress closely while receiving this medicine. This will help the doctor determine if the medicine is working properly. Blood and urine tests will be necessary to check for any unwanted effects.

Contact your doctor immediately if you or your child experience chest pain, cough, fainting, fast heartbeat, trouble breathing, or dizziness or lightheadedness after receiving this medicine. These could be signs of pulmonary embolism caused by precipitates found in the TPN solution, infusion set, and catheter.

Inform your doctor if you or your child have pain, tenderness, changes in skin color, or swelling of the foot or leg after receiving this medicine. These could be signs of vein damage or thrombophlebitis.

Seek immediate medical attention if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellowing of the eyes or skin. These could be signs of a serious liver problem.

In deciding to use a medicine, you and your doctor should consider the risks and benefits. For this medicine, keep the following in mind:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know about any other allergies, including food, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Studies have not shown any specific problems that would limit the use of cysteine injection in children. However, children may have immature kidney and liver functions, which may require caution when using this medicine.

Geriatric

There have not been studies on how age affects the use of cysteine injection in older adults. Safety and effectiveness have not been established.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication while breastfeeding. Consider the potential benefits and risks before taking this medication while breastfeeding.

Interactions with Medicines

Some medicines should not be used together. In other cases, two different medicines may be used together even if an interaction might happen. In these situations, your doctor may change the dose or take other precautions. Inform your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicines.

Interactions with Food/Tobacco/Alcohol

Some medicines should not be used around the time of eating food or certain types of food due to possible interactions. Using alcohol or tobacco with certain medicines may also lead to interactions. Discuss with your healthcare professional how to use your medicine with food, alcohol, or tobacco.

Other Medical Problems

Having other medical problems may affect how you can use this medicine. Be sure to tell your doctor about any other medical issues, especially:

• Acid-base imbalance or
• Electrolyte imbalance—These should be corrected before receiving this medicine.

• Acidosis (caused by low cardiac output) or
• Inborn errors of amino acid metabolism or
• Pulmonary edema (fluid in the lungs)—This medicine should not be used in patients with these conditions.

• Gallstones or
• Hyperammonemia (high ammonia levels in the blood) or
• Liver disease—Use with caution, as this may worsen these conditions.

• Kidney disease—Long-term use of this medicine in preterm babies may increase the risk of aluminum toxicity.

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

Check with your doctor or nurse right away if any of the following side effects occur:

Incidence not known

• Anxiety
• Chest pain
• Confusion
• Cough
• Dizziness or lightheadedness
• Drowsiness
• Fainting
• Fast heartbeat
• Feeling of warmth
• Fever
• Muscle tremors
• Nausea
• Pain, tenderness, or swelling of the foot or leg
• Rapid, deep breathing
• Redness of the face, neck, arms, and occasionally, upper chest
• Restlessness
• Stomach cramps
• Sudden shortness of breath or troubled breathing
• Unusual tiredness or weakness
• Warmth, redness, pain, or changes in skin color at the infusion site

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

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Nouress

Available Dosage Forms:

• Solution

Therapeutic Class: Amino Acid Supplement

A nurse or other trained health professional will give you or your child this medicine. Cysteine is added to your or your baby's TPN bag. After mixing, it is given through a needle placed in one of your or your baby's veins.

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