Generic Formulation - Azithromycin 250mg oral capsule - includes a reference to a substance in the Ingredient element (id = "med0320")

<?xml version="1.0" encoding="UTF-8"?>

<Medication xmlns="http://hl7.org/fhir">
  <id value="med0320"/> 
  <text> <status value="generated"/> <div xmlns="http://www.w3.org/1999/xhtml"><p> <b> Generated Narrative: Medication</b> <a name="med0320"> </a> </p> <div style="display: inline-block; background-color: #d9e0e7; padding: 6px; margin: 4px; border:
       1px solid #8da1b4; border-radius: 5px; line-height: 60%"><p style="margin-bottom: 0px">Resource Medication &quot;med0320&quot; </p> </div> <p> <b> code</b> : Azithromycin 250mg capsule (product) <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="https://browser.ihtsdotools.org/">SNOMED CT</a> #324252006)</span> </p> <p> <b> doseForm</b> : Tablet dose form (qualifier value) <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="https://browser.ihtsdotools.org/">SNOMED CT</a> #385055001)</span> </p> <blockquote> <p> <b> ingredient</b> </p> <h3> Items</h3> <table class="grid"><tr> <td> -</td> <td> <b> Reference</b> </td> </tr> <tr> <td> *</td> <td> <a name="sub03"> </a> <blockquote> <p/>  <p> <a name="sub03"> </a> </p> <p> <b> instance</b> : false</p> <h3> Codes</h3> <table class="grid"><tr> <td> -</td> <td> <b> Concept</b> </td> </tr> <tr> <td> *</td> <td> Azithromycin (substance) <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="https://browser.ihtsdotools.org/">SNOMED CT</a> #387531004)</span> </td> </tr> </table> </blockquote> </td> </tr> </table> <p> <b> strength</b> : 250 mg<span style="background: LightGoldenRodYellow"> (Details: UCUM code mg = 'mg')</span> /1(unit TAB from http://terminology.hl7.org/CodeSystem/v3-orderableDrugForm)<span style="background: LightGoldenRodYellow"> (Details: http://terminology.hl7.org/CodeSystem/v3-orderableDrugForm code TAB
             = 'Tablet')</span> </p> </blockquote> </div> </text> <contained> 
    <Substance> 
      <id value="sub03"/> 
      <instance value="false"/> 
      <code> 
        <concept> 
          <coding> 
            <system value="http://snomed.info/sct"/> 
            <code value="387531004"/> 
            <display value="Azithromycin (substance)"/> 
          </coding> 
        </concept> 
      </code> 
    </Substance> 
  </contained> 
  <code> 
    <coding> 
      <system value="http://snomed.info/sct"/> 
      <code value="324252006"/> 
      <display value="Azithromycin 250mg capsule (product)"/> 
    </coding> 
  </code> 
  
    <doseForm> 
      <coding> 
        <system value="http://snomed.info/sct"/> 
        <code value="385055001"/> 
        <display value="Tablet dose form (qualifier value)"/> 
      </coding> 
    </doseForm> 
    <ingredient> 
      <item> 
        <reference> 
        <reference value="#sub03"/> 
        </reference> 
      </item> 
      <strengthRatio> 
        <numerator> 
          <value value="250"/> 
          <system value="http://unitsofmeasure.org"/> 
          <code value="mg"/> 
        </numerator> 
        <denominator> 
          <value value="1"/> 
          <system value="http://terminology.hl7.org/CodeSystem/v3-orderableDrugForm"/> 
          <code value="TAB"/> 
        </denominator> 
      </strengthRatio> 
    </ingredient> 
  
</Medication>