A record of a medication that is being consumed by a patient. A MedicationStatement may indicate that the patient may be taking the medication now, or has taken the medication in the past or will be taking the medication in the future. The source of this information can be the patient, significant other (such as a family member or spouse), or a clinician. A common scenario where this information is captured is during the history taking process during a patient visit or stay. The medication information may come from e.g. the patient's memory, from a prescription bottle, or from a list of medications the patient, clinician or other party maintains

The primary difference between a medication statement and a medication administration is that the medication administration has complete administration information and is based on actual administration information from the person who administered the medication. A medication statement is often, if not always, less specific. There is no required date/time when the medication was administered, in fact we only know that a source has reported the patient is taking this medication, where details such as time, quantity, or rate or even medication product may be incomplete or missing or less precise. As stated earlier, the medication statement information may come from the patient's memory, from a prescription bottle or from a list of medications the patient, clinician or other party maintains. Medication administration is more formal and is not missing detailed information.

When interpreting a medicationStatement, the value of the status and NotTaken needed to be considered: MedicationStatement.status + MedicationStatement.wasNotTaken Status=Active + NotTaken=T = Not currently taking Status=Completed + NotTaken=T = Not taken in the past Status=Intended + NotTaken=T = No intention of taking Status=Active + NotTaken=F = Taking, but not as prescribed Status=Active + NotTaken=F = Taking Status=Intended +NotTaken= F = Will be taking (not started) Status=Completed + NotTaken=F = Taken in past Status=In Error + NotTaken=N/A = In Error.

External identifier - FHIR will generate its own internal identifiers (probably URLs) which do not need to be explicitly managed by the resource. The identifier here is one that would be used by another non-FHIR system - for example an automated medication pump would provide a record each time it operated; an administration while the patient was off the ward might be made with a different system and entered after the event. Particularly important if these records have to be updated.

A code representing the patient or other source's judgment about the state of the medication used that this statement is about. Generally this will be active or completed.

MedicationStatement is a statement at a point in time. The status is only representative at the point when it was asserted. The value set for MedicationStatement.status contains codes that assert the status of the use of the medication by the patient (for example, stopped or on hold) as well as codes that assert the status of the medication statement itself (for example, entered in error).

Identifies the medication being administered. This is either a link to a resource representing the details of the medication or a simple attribute carrying a code that identifies the medication from a known list of medications.

If only a code is specified, then it needs to be a code for a specific product. If more information is required, then the use of the medication resource is recommended. Note: do not use Medication.name to describe the medication this statement concerns. When the only available information is a text description of the medication, Medication.code.text should be used.

The person, animal or group who is/was taking the medication.

The interval of time during which it is being asserted that the patient was taking the medication (or was not taking, when the wasNotGiven element is true).

If the medication is still being taken at the time the statement is recorded, the "end" date will be omitted.

The person or organization that provided the information about the taking of this medication. Note: Use derivedFrom when a MedicationStatement is derived from other resources, e.g Claim or MedicationRequest.

Allows linking the MedicationStatement to the underlying MedicationRequest, or to other information that supports or is used to derive the MedicationStatement.

Likely references would be to MedicationRequest, MedicationDispense, Claim, Observation or QuestionnaireAnswers.

The date when the medication statement was asserted by the information source.

Indicator of the certainty of whether the medication was taken by the patient.

A code indicating why the medication was not taken.

A reason for why the medication is being/was taken.

This could be a diagnosis code. If a full condition record exists or additional detail is needed, use reasonForUseReference.

Condition or observation that supports why the medication is being/was taken.

This is a reference to a condition that is the reason why the medication is being/was taken. If only a code exists, use reasonForUseCode.

Provides extra information about the medication statement that is not conveyed by the other attributes.

Indicates where type of medication statement and where the medication is expected to be consumed or administered.

Indicates how the medication is/was used by the patient.