ICD-10 F05 is used for delirium due to a known physiological condition
The ICD-10-CM code F05 refers to delirium due to a known physiological condition. For behavioral health clinicians, this code may appear in documentation when a client presents with acute confusion, altered awareness, impaired attention, disorientation, fluctuating cognition, or behavioral changes connected to a medical condition.
This page is for documentation support, not diagnosis assignment. The clinician is responsible for selecting, confirming, and reviewing any diagnosis code used in the clinical record. AutoNotes does not assign diagnoses or replace clinical judgment. It can help organize session details into an editable note draft once the clinician has determined what belongs in the record.
Delirium documentation often sits at the intersection of mental health, medicine, neurology, substance use treatment, hospital discharge planning, and caregiver support. A therapist may not be the provider identifying the underlying medical cause, but the therapy note still needs to describe what the clinician observed, what the client reported, what collateral sources contributed, and what actions were taken during the session.
Clinical situations where F05 may appear in behavioral health documentation
F05 is most relevant when delirium is connected to a known physiological condition. In practice, a behavioral health provider may encounter this code after a client has been evaluated in a medical setting or when coordinating care with a physician, psychiatrist, hospital team, skilled nursing facility, or other treating provider.
Common documentation contexts include:
- Post-hospitalization follow-up where the client remains confused, disoriented, or unable to sustain attention.
- Medical illness, infection, metabolic disturbance, neurological condition, or medication-related concern noted by the medical team.
- Older adult clients with sudden cognitive changes that differ from their usual baseline.
- Caregiver or family reports of rapid changes in behavior, sleep-wake cycle, orientation, or awareness.
For example, a therapist may see a client one week after discharge from the hospital. The client is usually organized and verbally clear, but during the session they repeatedly lose track of the conversation, misidentify the day, and appear unsure why they are attending therapy. The note should not simply say “confused.” It should describe the observed change, how it affected participation, and what follow-up steps were taken.
What clinicians may need to document for delirium-related care
Strong delirium documentation is specific. It separates observable presentation from interpretation, identifies relevant clinical context, and shows how the clinician responded. This matters because delirium can fluctuate. A client may appear more oriented at the start of a session and more confused later, or a caregiver may report worsening symptoms at night even if the client presents more clearly during the appointment.
Presenting signs and observed behavior
Document what you can observe or reasonably assess during the encounter. This may include attention, awareness, speech, thought process, orientation, motor behavior, emotional presentation, and ability to participate in therapy.
Examples of useful language include:
- “Client required frequent redirection and lost track of the question several times.”
- “Client was oriented to person but not to date or location.”
- “Speech was intermittently tangential, with difficulty returning to the topic.”
- “Client appeared drowsy and had difficulty maintaining alertness during the session.”
These details are more clinically useful than broad terms such as “altered” or “not at baseline.” If baseline functioning is known, include the comparison. If it is not known, state that clearly.
Onset, course, and fluctuation
Delirium-related symptoms often develop over a short period and may shift throughout the day. Your documentation can note when symptoms reportedly began, whether they are improving or worsening, and whether the presentation changes across the session.
A concise entry might read: “Caregiver reported onset of confusion two days after medication change. Client appeared more alert during the first 15 minutes of session, then became increasingly distractible and disoriented.”
Known medical or physiological context
Because F05 refers to delirium due to a known physiological condition, the record should connect the mental status changes to the relevant medical context when that information is available. Behavioral health clinicians should avoid overstating medical conclusions outside their role. Instead, document the source of the information.
For example: “Client reported recent hospitalization for pneumonia,” “Discharge paperwork reviewed with client consent indicates delirium during admission,” or “Spouse reported client’s primary care provider is evaluating possible medication-related confusion.” This keeps the note accurate and transparent.
Progress note elements that support a clearer F05 record
A delirium-related progress note should show what happened in the session and why the clinician took specific actions. The exact format may vary by practice, payer, setting, and EHR, but most notes need enough detail to support clinical continuity.
Useful elements include the following:
- Subjective information: Client, caregiver, or collateral reports about confusion, sleep, orientation, mood, medical events, medication changes, safety concerns, or functional changes.
- Objective presentation: Clinician observations of attention, awareness, orientation, speech, behavior, affect, and ability to engage.
- Clinical assessment: How the presentation affected the session, whether symptoms appear changed from baseline, and any relevant risk or care coordination needs.
- Plan: Follow-up steps, referrals, coordination with medical providers, caregiver involvement, safety planning, or changes to session structure.
In a SOAP note, these details may fall into the Subjective, Objective, Assessment, and Plan sections. In a DAP note, they may appear under Data, Assessment, and Plan. The format matters less than the clarity of the clinical story.
Sample progress note language for delirium-related documentation
The following example is for documentation style only. It is not a diagnostic template, and it should be edited to match the clinician’s actual findings, scope, setting, and client presentation.
Sample SOAP note excerpt
Subjective: Client attended session with spouse present by client consent. Spouse reported that client has been “more confused than usual” since hospital discharge three days ago and has been waking during the night unsure of location. Client stated, “I don’t know why I’m here,” and had difficulty describing recent events. Client denied current intent to harm self or others when asked directly, though responses required repetition and clarification.
Objective: Client appeared tired and intermittently disoriented. Oriented to person, inconsistently oriented to place, and not oriented to date. Client required frequent redirection and repeated two questions multiple times. Speech was soft and slowed. Affect appeared constricted. Client had difficulty sustaining attention for more than brief periods, limiting ability to participate in standard psychotherapy interventions.
Assessment: Presentation reflected acute cognitive and attentional changes reported after recent hospitalization. Session focus shifted from insight-oriented work to supportive assessment, orientation, caregiver involvement, and care coordination. Clinician did not independently determine the medical cause of symptoms. Client’s spouse reported follow-up appointment with primary care tomorrow.
Plan: Encouraged spouse to contact medical provider sooner if confusion worsens or if safety concerns emerge. With client consent, clinician will coordinate with prescribing provider regarding observed presentation. Next session will use shorter check-ins, written reminders, and caregiver-supported orientation as clinically appropriate. Continue to monitor mental status, risk, and ability to participate in therapy.
Treatment planning considerations when delirium affects therapy
Delirium can limit a client’s ability to engage in standard psychotherapy. The treatment plan may need short-term adjustments while medical evaluation and stabilization occur. Goals should be realistic for the client’s current cognitive capacity and should avoid implying that psychotherapy alone treats the underlying physiological condition.
Documentation may include goals such as improving safety awareness, supporting orientation, reducing distress related to confusion, involving caregivers appropriately, and coordinating with medical providers. Interventions may include grounding, environmental supports, psychoeducation for family members, brief supportive counseling, reality orientation, and monitoring changes in presentation.
A treatment plan update might include:
- Goal: Support client safety and emotional regulation during period of acute confusion.
- Intervention: Provide brief grounding and orientation prompts during sessions as tolerated.
- Care coordination: Obtain consent to communicate with medical or psychiatric providers when clinically indicated.
- Monitoring: Track changes in attention, orientation, sleep disruption, agitation, and caregiver-reported concerns.
If the client cannot meaningfully participate in therapy, document the limitation and the clinical response. For example, a clinician may shorten the session, involve a caregiver with consent, recommend urgent medical follow-up, or focus on safety and support rather than deeper therapeutic processing.
Related coding issues clinicians should review carefully
Delirium coding can be more complex than a single code. F05 is specific to delirium due to a known physiological condition, but delirium-like symptoms may also appear in substance intoxication, withdrawal, dementia, medication reactions, psychosis, mood episodes, traumatic brain injury, and other medical or psychiatric contexts.
Behavioral health clinicians should avoid selecting F05 solely because a client appears confused. The note should support the clinical picture, and the diagnosis should reflect the clinician’s assessment, available information, payer requirements, and applicable coding guidance. If another provider has established the diagnosis, document that source. If the condition is outside your diagnostic role or scope, document observations and care coordination rather than making unsupported conclusions.
Be especially careful with substance-related presentations. Delirium associated with intoxication or withdrawal may require different coding depending on the substance, clinical context, and coding system in use. If you are unsure, consult your organization’s coding support, billing specialist, supervisor, or relevant payer guidance.
Common documentation pitfalls with delirium
Several note-writing habits can make delirium documentation less useful. The goal is not to write longer notes. The goal is to write notes that make the clinical situation understandable to another treating professional.
- Using vague labels: “Confused” is less helpful than describing orientation, attention, speech, and behavior.
- Skipping baseline comparison: If the client’s usual functioning is known, document how the current presentation differs.
- Overstating causation: Avoid saying a medical condition caused the delirium unless that determination is supported and within your role.
- Leaving out coordination: If medical follow-up, caregiver contact, or provider collaboration occurred, include it in the plan.
Good documentation also avoids making the note sound more certain than the clinical facts allow. Phrases such as “reported by spouse,” “per discharge paperwork,” “client stated,” and “clinician observed” help distinguish sources of information.
How AutoNotes supports editable delirium documentation drafts
AutoNotes helps clinicians create structured, editable progress note drafts from session details. For delirium-related documentation, that structure can help organize observations, collateral information, clinical assessment, interventions, and follow-up steps without forcing the clinician into a generic note format.
For example, a therapist can enter session details such as observed disorientation, caregiver report, recent hospitalization, interventions used, risk assessment, and care coordination plan. AutoNotes can then help produce a draft in a format such as SOAP, DAP, or another service-specific note structure. The clinician reviews, edits, and finalizes the note before it becomes part of the clinical record.
This distinction matters. AutoNotes does not diagnose delirium, choose ICD-10 codes for the clinician, or determine medical causation. It supports the documentation workflow by giving clinicians a more organized starting point, especially when the session includes multiple moving pieces such as cognitive changes, collateral reports, safety concerns, and provider coordination.
Use F05 documentation to make the clinical record clearer
Delirium-related notes need to communicate more than a code. They should show the client’s presentation, the known medical context, the clinician’s observations, the limits of the session, and the plan for follow-up. Clear documentation can help the next provider understand what changed, what was assessed, and what needs attention.
If documentation is taking too much time after sessions, AutoNotes can help create structured, editable drafts for progress notes, assessments, treatment planning, and other behavioral health documentation. The clinician stays in control of reviewing the content and making the final clinical decision.
Start your free trial to try AutoNotes with your own documentation workflow.
