Generic Name: lactase enzyme
Brand Names: Lactaid Original, Colief, Lactaid Fast Act Chewables, Lactaid Fast Act Caplets
Drug Class: Nutritionals, Other
What is lactase enzyme, and what is it used for?
Lactase is a digestive enzyme that breaks up lactose, the carbohydrate in milk and milk products. Carbohydrates have to be broken into simple forms of sugars for cells to be able to use them for energy. Lactase enzyme breaks lactose into glucose and galactose, simple sugars that can be absorbed by the small intestines. Lactase enzyme is available as oral tablets and solutions over the counter (OTC).
If lactose is not broken down in the intestines and large amounts of lactose pass into the colon, the bacteria in the colon break lactose down and this can cause gas, bloating and diarrhea. Some people of less lactase due to genetic conditions or certain gastrointestinal conditions and are unable to digest lactose. Lactose intolerant adults and children can take lactase enzyme as a supplement to help digest milk products.
Warnings
- Do not administer lactase to children younger than 4 years of age without checking with a pediatrician.
- Some lactase enzyme products may contain aspartame, which should be avoided by people with phenylketonuria, a condition that causes inability to breakdown phenylalanine, an amino acid that aspartame contains.
- Rarely, some people may have allergic reaction to lactase.
What are the side effects of lactase enzyme?
Lactase enzyme has no documented side effects.
Some people may have an allergic reaction.
Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:
- Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
- Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
- Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
- Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.

QUESTION
Pancreatitis is inflammation of an organ in the abdomen called the pancreas. See AnswerWhat are the dosages of lactase enzyme?
Expressed in Food Chemical Codex (FCC) units
1 mg is equivalent to 14 FCC units
Tablet
- 3,000 units/tablet (Lactaid Original)
- 9,000 units/tablet (Lactaid Fast Act Caplets)
Chewable tablet
- 9,000 units/tablet (Lactaid Fast Act Chewables)
Oral Solution
- Colief Infant Drops
Adult:
- Take 3,000-9,000 units orally with meals or dairy
Dosing considerations
- If still eating or drinking dairy products after 30-45 minutes, may need to take another dose as per recommendations of healthcare professional
Pediatric:
Lactose Intolerance
- Children 4 years and older: Take 3,000-9,000 units orally with meals or dairy
Infant Colic
- Express a few tablespoons of breast milk into a sterilized container
- Add 4 drops of lactase infant drops
- Give mixture to infant on a spoon or oral syringe before initiating breastfeeding
- Breastfeed as normal
Formula
- Prepare infant's formula as per manufacturer's instructions (or use ready-to-use formula)
- Add 4 drops of lactase infant drops to warm (not hot) formula
- Wait 30 minutes, shaking the formula occasionally, then feed your infant as normal, making sure that the formula is at the correct temperature
- Discard any unused formula
Making formula in advance with lactase infant drops
- Prepare infant's formula as per manufacturer's instructions
- Add 2 drops of lactase infant drops to the warm (not hot) formula
- Store in your refrigerator for a minimum of 4 hours before use and use within 12 hours
- Feed infant as normal making sure that the formula is at the correct temperature
- Discard any unused formula
Dosing Considerations
- Children below 4 years of age to be administered only under supervision of healthcare professional
Administration
- Lactase enzyme is destroyed by high heat; it works best in warm milk/formula (i.e., body temperature approximately 98 degrees F).
- Add lactase infant drops after milk/formula is prepared and at body temperature; do not boil milk with the lactase drops already mixed in with the milk.
Overdose
- There are no reports of toxic effects from lactase enzyme and overdose is unlikely to cause any adverse effects.
- If you have an allergic reaction, discontinue lactase and notify Poison Control.
What drugs interact with lactase enzyme?
Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.
- Lactase enzyme has no known severe, serious, moderate or mild interactions with other drugs.
The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.
It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.
Pregnancy and breastfeeding
- Lactase enzyme is likely safe in recommended doses with appropriate lactose foods during pregnancy and breastfeeding.
- Check with your healthcare provider before taking any supplement if you are pregnant or breastfeeding.
What else should I know about lactase enzyme?
- Take lactase enzyme exactly as per label instructions.
- Lactase enzyme is generally recognized as safe for consumption.
- Dietary supplements often contain many ingredients. Check labels for the components in the lactase enzyme product you choose.
- Lactase enzyme is marketed as a dietary supplement and does not require pre-marketing approvals from the FDA. Products may differ in formulations and strengths, and labels may not always match contents; exercise caution in choosing your product.
Summary
Lactase is a digestive enzyme that breaks up lactose, the carbohydrate in milk and milk products. Lactose intolerant adults and children can take lactase enzyme as a supplement to help digest milk products. Do not administer lactase to children younger than 4 years of age without checking with a pediatrician. Lactase enzyme has no documented side effects. Some people may have an allergic reaction. Consult your doctor if you are pregnant or breastfeeding.
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Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
https://www.rxlist.com/consumer_lactaid_lactase_enzyme/drugs-condition.htm
https://reference.medscape.com/drug/lactaid-original-colief-lactase-enzyme-999958#0
https://www.uptodate.com/contents/lactase-drug-information
https://www.webmd.com/drugs/2/drug-5506/lactase-enzyme-oral/details
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4153634/