Z51.81
BillableEncounter for therapeutic drug level monitoring
Encounter for therapeutic drug level monitoring
Coding Notes
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- follow-up examination for medical surveillance after treatment (Z08-Z09)
Code Also
A second code may be required; sequencing depends on circumstances
- condition requiring care
- any long-term (current) drug therapy (Z79.-)
Also Known As / Clinical Terms
SNOMED CT
- Ineffective drug action58848006
- Lack of drug action58848006
- Lack of drug effect58848006
- Drug action increased95899007
- Drug effect increased95899007
- Drug action decreased95900002
- Drug effect decreased95900002
- Drug action prolonged95901003
- Drug effect prolonged95901003
- Drug action shortened95902005
- Drug effect shortened95902005
- Drug action reversal95913008
- Drug effect reversal95913008
- Effects of immunotherapy109954009
- Therapeutic action of medication110280000
- Therapeutic drug action110280000
- Therapeutic drug effect110280000
- Phenobarbital level therapeutic166938002
- Phenobarbitone level therapeutic166938002
- Phenobarbital level low166939005
- Phenobarbitone level below therapeutic range166939005
- Phenobarbitone level low166939005
- Phenobarbital level high166940007
- Phenobarbitone level above therapeutic range166940007
- Phenobarbitone level high166940007
- Phenytoin level below reference range166942004
- Phenytoin level low166942004
- Phenytoin level therapeutic166943009
- Phenytoin level above therapeutic range166944003
- Phenytoin level high166944003
- Carbamazepine level therapeutic166950008
- Carbamazepine level below reference range166951007
- Carbamazepine level low166951007
- Carbamazepine level above reference range166952000
- Carbamazepine level high166952000
- Lithium level therapeutic166956002
- Lithium level below therapeutic range166958001
- Lithium level low166958001
- Digoxin level therapeutic166960004
- Digoxin level below therapeutic range166961000
- Digoxin level low166961000
- Digoxin level above therapeutic range166963002
- Digoxin level high166963002
- Intermittent drugs used more170611001
- Inhaler technique - poor170626004
- Bronchodilators used more than once daily170629006
- Bronchodilators used a maximum of once daily170630001
- Pre-treatment uric acid level170734001
- Hormone replacement monitoring check done185917005
- PEM completed185927004
- Prescription event monitoring completed185927004
- Prescription-event monitoring (PEM) completed185927004
- Gout monitoring status243859006
- Warfarin monitoring status243873002
- Bronchodilators used once daily274411003
- Phenothiazine injection - monitor275916009
- Asthma monitoring status308501009
- Hormone replacement monitoring status308534006
- Prescription event monitoring status309035009
- Aminophylline level365730009
- Aminophylline level - finding365730009
- Finding of aminophylline level365730009
- Aminophylline: blood level365731008
- Aminophylline: blood level - finding365731008
- Finding of aminophylline: blood level365731008
- Finding of serum aminophylline level365732001
- Serum aminophylline level365732001
- Serum aminophylline level - finding365732001
- Carbamazepine level365733006
- Carbamazepine level - finding365733006
- Finding of carbamazepine level365733006
- Finding of serum carbamazepine level365734000
- Serum carbamazepine level365734000
- Serum carbamazepine level - finding365734000
- Digoxin level365735004
- Digoxin level - finding365735004
- Finding of digoxin level365735004
- Finding of serum digoxin level365736003
- Serum digoxin level365736003
- Serum digoxin level - finding365736003
- Finding of lithium level365738002
- Lithium level365738002
- Lithium level - finding365738002
- Finding of blood lithium level365739005
- Lithium: blood level365739005
- Lithium: blood level - finding365739005
- Finding of serum lithium level365740007
- Serum lithium level365740007
- Serum lithium level - finding365740007
- Finding of phenobarbitone level365741006
- Phenobarbitone level365741006
- Phenobarbitone level - finding365741006
- Finding of serum phenobarbital level365742004
- Finding of serum phenobarbitone level365742004
- Serum phenobarbitone level365742004
- Serum phenobarbitone level - finding365742004
- Finding of phenytoin level365743009
- Phenytoin level365743009
- Phenytoin level - finding365743009
- Finding of serum phenytoin level365744003
- Serum phenytoin level365744003
- Serum phenytoin level - finding365744003
- Finding of valproate level365745002
- Valproate level365745002
- Valproate level - finding365745002
- Finding of serum sodium valproate level365746001
- Serum sodium valproate level365746001
- Serum sodium valproate level - finding365746001
- Inhaler technique - moderate390869002
- Nebuliser technique good391106002
- Nebulizer technique good391106002
- Nebuliser technique poor391107006
- Nebulizer technique poor391107006
- No nebulisation since last appointment401190001
- No nebulization since last appointment401190001
- Drug monitoring up to date408362004
- Medication monitoring up to date408362004
- Antihypertensive agent surveillance done709596006
- Antihypertensive medication surveillance done709596006
- Good response to medication1137679005
- Serum sodium valproate within therapeutic range1156005004
- Serum sodium valproate above therapeutic range1156006003
- Serum sodium valproate below therapeutic range1156007007
- Serum lithium level within therapeutic range1156020005
- Serum lithium level above therapeutic range1156021009
- Serum lithium level below therapeutic range1156022002
- Serum digoxin level above therapeutic range1156024001
- Serum digoxin level within therapeutic range1156025000
- Serum digoxin level below therapeutic range1156026004
- Serum phenytoin above therapeutic range1156043001
- Serum phenytoin within therapeutic range1156044007
- Serum phenytoin below therapeutic range1156045008
- Serum phenobarbital above therapeutic range1156056008
- Serum phenobarbitone above therapeutic range1156056008
- Serum phenobarbital below therapeutic range1156057004
- Serum phenobarbitone below therapeutic range1156057004
- Serum phenobarbital within therapeutic range1156058009
- Serum phenobarbitone within therapeutic range1156058009
- Serum carbamazepine above therapeutic range1156061005
- Serum carbamazepine below therapeutic range1156062003
- Serum carbamazepine within therapeutic range1156063008
- Acetaminophen within therapeutic range1172948006
- Paracetamol within therapeutic range1172948006
- Acetaminophen above therapeutic range1172949003
- Paracetamol above therapeutic range1172949003
- Salicylate above therapeutic range1187051004
- Salicylate below therapeutic range1187169005
- Serum aminophylline within therapeutic range1187175001
- Serum aminophylline above therapeutic range1187176000
- Serum aminophylline below therapeutic range1187177009
- Measurement of medication level in blood started448201000124101
- Medication dose changed432751000124106
- Medication dose changed in response to liver function453301000124104
- Medication dose changed in response to renal function453291000124100
- Medication dose changed to sliding scale453831000124103
- Medication dose changed too rapidly453461000124109
- Medication therapy changed too rapidly432361000124107
Frequently Asked Questions
What is ICD-10 code Z51.81?
ICD-10-CM code Z51.81 represents "Encounter for therapeutic drug level monitoring". It is a billable/specific code that can be used on a claim.
Is Z51.81 a billable code?
Yes, Z51.81 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.
What chapter is Z51.81 in?
Z51.81 is in Chapter 22: Factors Influencing Health Status and Contact With Health Services (codes Z00-Z99).
What codes cannot be used with Z51.81?
Z51.81 has Excludes1 notes indicating codes that cannot be used together with it, including: follow-up examination after treatment (Z08-Z09); holiday relief care (Z75.5); encounter for blood-drug test for administrative or medicolegal reasons (Z02.83).
What SNOMED CT codes does Z51.81 map to?
Z51.81 maps to 91 SNOMED CT concepts: 1172949003, 1172948006, 365730009, 365731008, 709596006, and 86 more. SNOMED CT is a clinical terminology used in electronic health records.
What are the UMLS CUIs for Z51.81?
Z51.81 is linked to 1 UMLS Concept Unique Identifier: C2910943. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.