Magnesium hydroxide 80 mg/ML Oral Suspension [Ex-Lax Milk of Magnesia]
RxNorm 351631

Concept Hierarchy & Relationship Mapping

RxNorm Concept Unique Identifier (RxCUI) 351631 represents a standardized clinical drug concept used for cross-system interoperability. This concept aggregates multiple Atom IDs (AUIs), which are specific naming variations and synonyms used across pharmaceutical databases to ensure accurate medication mapping for: magnesium hydroxide 80 mg/ML Oral Suspension [Ex-Lax Milk of Magnesia].

The following semantic concepts and normalized strings are associated with this clinical entity:

SY
Ex-Lax Milk of Magnesia 400 mg per 5 mL Oral Suspension
AUI:3607377
View
SY
Ex-Lax Milk of Magnesia 8 % Oral Suspension
AUI:2995169
View
SY
Ex-Lax Milk of Magnesia 80 mg/ML Oral Suspension
AUI:1549328
View
SBD
Magnesium hydroxide 80 mg/ML Oral Suspension [Ex-Lax Milk of Magnesia]
AUI:12357298
View

This clinical crossover tool is designed for healthcare professionals, pharmacists, and data analysts to safely compare substitute products and manage medication interoperability.

SY

Synonym (SY):
Ex-Lax Milk of Magnesia 400 mg per 5 mL Oral Suspension
(Atom ID: 3607377)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Ex-Lax Milk of Magnesia 400 MG per 5 ML Oral Suspension
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
351631
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
3607377
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SY
Synonym (Synonym of another TTY, given for clarity.)
Source Code
351631
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
RxNorm Vocabulary (RXNORM)
The official name and abbreviation for the vocabulary source.
Source Version
20AA_260601F
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
RxNorm Customer Service, , U.S. National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, (888) FIND-NLM, , https://support.nlm.nih.gov/support/create-case/, https://www.nlm.nih.gov/research/umls/rxnorm/
Source licensing contact information.
SY

Synonym (SY):
Ex-Lax Milk of Magnesia 8 % Oral Suspension
(Atom ID: 2995169)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Ex-Lax Milk of Magnesia 8 % Oral Suspension
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
351631
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
2995169
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SY
Synonym (Synonym of another TTY, given for clarity.)
Source Code
351631
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
RxNorm Vocabulary (RXNORM)
The official name and abbreviation for the vocabulary source.
Source Version
20AA_260601F
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
RxNorm Customer Service, , U.S. National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, (888) FIND-NLM, , https://support.nlm.nih.gov/support/create-case/, https://www.nlm.nih.gov/research/umls/rxnorm/
Source licensing contact information.
SY

Synonym (SY):
Ex-Lax Milk of Magnesia 80 mg/ML Oral Suspension
(Atom ID: 1549328)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
Ex-Lax Milk of Magnesia 80 MG/ML Oral Suspension
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
351631
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
1549328
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SY
Synonym (Synonym of another TTY, given for clarity.)
Source Code
351631
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
RxNorm Vocabulary (RXNORM)
The official name and abbreviation for the vocabulary source.
Source Version
20AA_260601F
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
RxNorm Customer Service, , U.S. National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, (888) FIND-NLM, , https://support.nlm.nih.gov/support/create-case/, https://www.nlm.nih.gov/research/umls/rxnorm/
Source licensing contact information.
SBD

Semantic Branded Drug (SBD):
Magnesium hydroxide 80 mg/ML Oral Suspension [Ex-Lax Milk of Magnesia]
(Atom ID: 12357298)

Clinical Status & Identity

Prescribable Status
NO (Reference)
Part of the RxNorm Current Prescribable Content subset including all drugs available for prescription in the USA.
Concept Description
magnesium hydroxide 80 MG/ML Oral Suspension [Ex-Lax Milk of Magnesia]
Official description of the drug concept as defined in the source vocabulary.
Suppress Flag
O
N: Not suppressible | O: Obsolete | Y: Suppressed by editor | E: Unquantified non-prescribable drug.

Interoperability & Coding

Concept ID (RxCUI)
351631
RxNorm Unique Identifier for the standardized concept.
Atom ID (RXAUI)
12357298
Unique identifier for this specific name variation (Atom).
Term Type (TTY)
SBD
Semantic Branded Drug (Ingredient + Strength + Dose Form + Brand Name)
Source Code
351631
The "Most useful" identifier asserted by the original source vocabulary.

Source & Registry Data

Source Name
RxNorm Vocabulary (RXNORM)
The official name and abbreviation for the vocabulary source.
Source Version
20AA_260601F
The specific version of the vocabulary provided by the source.
Update Date
June 01, 2026
The date when this RxNorm data was last updated by the NLM.
License Contact
RxNorm Customer Service, , U.S. National Library of Medicine, 8600 Rockville Pike, , Bethesda, MD, United States, 20894, (888) FIND-NLM, , https://support.nlm.nih.gov/support/create-case/, https://www.nlm.nih.gov/research/umls/rxnorm/
Source licensing contact information.

Technical Attributes & Logic

RXN AI
{316211} 6581
RXCUI of BOSS Active Ingredient preceded by RXCUI of SCDC responsible for value
RXN AM
{316211} 1314279
RXCUI of BOSS Active Moiety preceded by RXCUI of SCDC responsible for value
RXN BOSS FROM
{316211} AI
Source of BOSS as either from the active ingredient (AI) or the active moiety (AM) preceded by RXCUI of SCDC responsible for value
RXN OBSOLETED
07/26/2022
Date the RxNorm atom became obsolete
RXTERM FORM
Susp
The RxTerm dose form name for this drug

Patient Education

Magnesium Hydroxide


Magnesium hydroxide is used to treat occasional constipation in children and adults on a short-term basis. Magnesium hydroxide is in a class of medications called saline laxatives. It works by causing water to be retained with the stool. This increases the number of bowel movements and softens the stool so it is easier to pass.
[Learn More]


* Please review the disclaimer below.