This code system http://terminology.hl7.org/CodeSystem/medicationrequest-status-reason defines the following codes:

CodeDisplayDefinition
altchoice Try another treatment firstThis therapy has been ordered as a backup to a preferred therapy. This order will be released when and if the preferred therapy is unsuccessful.
clarif Prescription requires clarificationClarification is required before the order can be acted upon.
drughigh Drug level too highThe current level of the medication in the patient's system is too high. The medication is suspended to allow the level to subside to a safer level.
hospadm Admission to hospitalThe patient has been admitted to a care facility and their community medications are suspended until hospital discharge.
labint Lab interference issuesThe therapy would interfere with a planned lab test and the therapy is being withdrawn until the test is completed.
non-avail Patient not availablePatient not available for a period of time due to a scheduled therapy, leave of absence or other reason.
preg Parent is pregnant/breast feedingThe patient is pregnant or breast feeding. The therapy will be resumed when the pregnancy is complete and the patient is no longer breastfeeding.
salg AllergyThe patient is believed to be allergic to a substance that is part of the therapy and the therapy is being temporarily withdrawn to confirm.
sddi Drug interacts with another drugThe drug interacts with a short-term treatment that is more urgently required. This order will be resumed when the short-term treatment is complete.
sdupther Duplicate therapyThe drug interacts with a short-term treatment that is more urgently required. This order will be resumed when the short-term treatment is complete.
sintol Suspected intoleranceThe drug interacts with a short-term treatment that is more urgently required. This order will be resumed when the short-term treatment is complete.
surg Patient scheduled for surgery.The drug is contraindicated for patients receiving surgery and the patient is scheduled to be admitted for surgery in the near future. The drug will be resumed when the patient has sufficiently recovered from the surgery.
washout Waiting for old drug to wash outThe patient was previously receiving a medication contraindicated with the current medication. The current medication will remain on hold until the prior medication has been cleansed from their system.
<status value="draft"/> <experimental value="false"/> <date value="2021-12-02T19:54:18-07:00"/> <publisher value="FHIR Project team"/> <contact> <telecom> <system value="url"/> <value value="http://hl7.org/fhir"/> </telecom> </contact> <description value="MedicationRequest Status Reason Codes"/> <caseSensitive value="true"/> <valueSet value="http://terminology.hl7.org/ValueSet/medicationrequest-status-reason"/> <content value="complete"/> <concept> <code value="altchoice"/> <display value="Try another treatment first"/> <definition value="This therapy has been ordered as a backup to a preferred therapy. This order will be released when and if the preferred therapy is unsuccessful."/> </concept> <concept> <code value="clarif"/> <display value="Prescription requires clarification"/> <definition value="Clarification is required before the order can be acted upon."/> </concept> <concept> <code value="drughigh"/> <display value="Drug level too high"/> <definition value="The current level of the medication in the patient's system is too high. The medication is suspended to allow the level to subside to a safer level."/> </concept> <concept> <code value="hospadm"/> <display value="Admission to hospital"/> <definition value="The patient has been admitted to a care facility and their community medications are suspended until hospital discharge."/> </concept> <concept> <code value="labint"/> <display value="Lab interference issues"/> <definition value="The therapy would interfere with a planned lab test and the therapy is being withdrawn until the test is completed."/> </concept> <concept> <code value="non-avail"/> <display value="Patient not available"/> <definition value="Patient not available for a period of time due to a scheduled therapy, leave of absence or other reason."/> </concept> <concept> <code value="preg"/> <display value="Parent is pregnant/breast feeding"/> <definition value="The patient is pregnant or breast feeding. The therapy will be resumed when the pregnancy is complete and the patient is no longer breastfeeding."/> </concept> <concept> <code value="salg"/> <display value="Allergy"/> <definition value="The patient is believed to be allergic to a substance that is part of the therapy and the therapy is being temporarily withdrawn to confirm."/> </concept> <concept> <code value="sddi"/> <display value="Drug interacts with another drug"/> <definition value="The drug interacts with a short-term treatment that is more urgently required. This order will be resumed when the short-term treatment is complete."/> </concept> <concept> <code value="sdupther"/> <display value="Duplicate therapy"/> <definition value="The drug interacts with a short-term treatment that is more urgently required. This order will be resumed when the short-term treatment is complete."/> </concept> <concept> <code value="sintol"/> <display value="Suspected intolerance"/> <definition value="The drug interacts with a short-term treatment that is more urgently required. This order will be resumed when the short-term treatment is complete."/> </concept> <concept> <code value="surg"/> <display value="Patient scheduled for surgery."/> <definition value="The drug is contraindicated for patients receiving surgery and the patient is scheduled to be admitted for surgery in the near future. The drug will be resumed when the patient has sufficiently recovered from the surgery."/> </concept> <concept> <code value="washout"/> <display value="Waiting for old drug to wash out"/> <definition value="The patient was previously receiving a medication contraindicated with the current medication. The current medication will remain on hold until the prior medication has been cleansed from their system."/> </concept> </CodeSystem>