Syncope and collapse (R55)
ICD-10 code R55 is used to classify episodes of syncope and collapse, which refer to a temporary loss of consciousness or fainting. It captures a variety of conditions where an individual experiences sudden, brief inability to stay conscious, often due to reduced blood flow to the brain.
This code encompasses many related terms such as vasovagal syncope (including elderly vasovagal syndrome and situational syncope like micturition or defecation syncope), as well as other types like cardiac syncope, hypotensive syncope, and convulsive syncope. Common synonyms like “brief loss of consciousness,” “near syncope,” and “collapse” guide coders in selecting R55 when medical records describe these events. The term also covers unusual triggers such as syncope caused by immersion or centrifugal force during flying. Using R55 helps medical professionals accurately document and differentiate syncope from other causes of loss of consciousness for proper diagnosis and reporting.
Instructional Notations
Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
- Blackout
- Fainting
- Vasovagal attack
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- cardiogenic shock R57.0
- carotid sinus syncope G90.01
- heat syncope T67.1
- neurocirculatory asthenia F45.8
- neurogenic orthostatic hypotension G90.3
- orthostatic hypotension I95.1
- postprocedural shock T81.1
- psychogenic syncope F48.8
- shock NOS R57.9
- shock complicating or following abortion or ectopic or molar pregnancy O00 O07 O08.3
- shock complicating or following labor and delivery O75.1
- Stokes-Adams attack I45.9
- unconsciousness NOS R40.2
Clinical Terms
The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.
Brain Ischemia
Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.
Heat Stress Disorders
A group of conditions that develop due to overexposure or overexertion in excessive environmental heat.
Syncope
A transient loss of consciousness and postural tone caused by diminished blood flow to the brain (i.e., BRAIN ISCHEMIA). Presyncope refers to the sensation of lightheadedness and loss of strength that precedes a syncopal event or accompanies an incomplete syncope. (From Adams et al., Principles of Neurology, 6th ed, pp367-9)
Syncope, Vasovagal
Loss of consciousness due to a reduction in blood pressure that is associated with an increase in vagal tone and peripheral vasodilation.
