Lactase
Lactase is an enzyme supplement that helps individuals digest lactose, the sugar found in milk and dairy products. It is primarily used by people with lactose intolerance.
Lactase is an enzyme supplement used to help people with lactose intolerance digest dairy products by breaking down the milk sugar lactose.
Key facts at a glance
- ATC
- A09AA04
- RxNorm
- 41397
- Generic
- Lactase
- Class
- atc-a09
- Brands
- Beano Dairy Defense, Lactaid
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet, capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
first trimesterno adjustment needed
use as directed with food when consuming dairy products
standard prenatal care
pregnancy
third trimesterno adjustment needed
continue use as needed for lactose-containing foods
standard prenatal care
lactation
breastfeedingno adjustment needed
safe to use when consuming dairy products while breastfeeding
none required
pediatric_age
infantsuse infant-specific formulations
consult pediatrician before use in infants under 2 years
monitor for digestive symptoms
Use with caution and monitor for adverse effects.
pediatric_age
childrenuse age-appropriate dosing
safe for children over 2 years when used as directed with dairy
standard pediatric care
geriatric
elderlyno adjustment needed
safe for use in elderly populations
none required
renal_impairment
mild to moderateno adjustment needed
safe to use - not renally excreted
none required
hepatic_impairment
mild to moderateno adjustment needed
safe to use - not hepatically metabolized
none required
Statistics and clinical data
Commonly prescribed since
General prescribing information
Drug class
Drug class information
Common uses
Common therapeutic uses
Mechanism of action
How the medication works
Lactase deficiency and lactose intolerance, allowing individuals to consume milk and dairy products without experiencing typical symptoms like bloating, gas, cramping, and diarrhea. It may also be used in infants with temporary lactase deficiency.
Lactase is an enzyme that hydrolyzes (breaks down) lactose into its two component sugars: glucose and galactose. These simpler sugars can then be easily absorbed by the small intestine. Taking lactase supplements with dairy foods provides the enzyme needed to complete this digestion process that the body cannot perform adequately on its own.
Lactase supplements should be taken at the start of consuming dairy products for best results. They are generally safe for most people but are not suitable for individuals with galactosemia. Effectiveness varies by person depending on the degree of lactase deficiency and the amount of dairy consumed. Always read product labeling as formulations and strengths may vary.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 20, 2026. · Read our editorial policy