Shock
In a medical emergency, "shock" does not mean the everyday reaction to bad news it refers to a potentially life-threatening condition that can have different causes. Because shock can be fatal, quick action is essential.
Basically, shock is the body's emergency program. It tries to keep blood flow to the vital organs by reducing blood flow to the periphery the arms and legs. This happens when the blood vessels in the limbs constrict and is called centralization. This response is useful if there is major blood loss or a lot of fluid is leaking from the blood vessels into surrounding tissue. However, metabolic reactions can cause more fluid to leak into tissues or bleeding to occur elsewhere in the body, which further reduces the circulating blood volume. Doctors call this the vicious cycle of shock. It is hard to stop and can lead to full circulatory collapse and multiple organ failure. That's why early recognition and intervention are so important.
How can I recognize shock?
There are general signs of shock such as
- restlessness, nervousness, anxiety
- paleness
- clammy/sweaty
- feeling cold, possibly shivering
- low blood pressure
- fast pulse that is hard to feel
- rapid breathing
- bluish lips
- later: listlessness, fainting
Depending on the type of shock, the symptoms can vary a bit. Below you will find the different types of shock, how to recognize them, and how you can help the affected person. Not all signs are always present!
What to do if someone is in shock?
There are several general measures that apply to most types of shock. We describe specific actions for certain shock types below. Please note the exceptions where the shock position is not appropriate.
- Stay with the person talk to them and calm them.
- If necessary, stop any bleeding.
- Place them in the shock position (lying flat, legs elevated) if there is no exception.
- Keep them warm: cover the person. You can also place a blanket (emergency blanket) under them.
- Call emergency services or make sure someone else does.
- Keep checking their level of consciousness and breathing regularly.
Exceptions where the shock position should not be used
- heart disease, difficulty breathing (see cardiogenic shock)
- head injuries
- spinal injuries
- injuries to the chest or abdomen
- fractures of the pelvis or legs
- severe hypothermia
What types of shock are there?
Shock can have different causes and is therefore divided into
- neurogenic shock (vasovagal syncope as a special form)
- cardiogenic shock
- volume-loss shock (hypovolemic shock)
- allergic shock (anaphylactic shock)
- septic shock
- other types of shock
Neurogenic shock (shock affecting the nervous system)
Neurogenic shock is a disturbance of the central regulation of circulation. There is an imbalance between the sympathetic and parasympathetic regulation of heart function and vascular muscle. This causes a generalized widening of the blood vessels throughout the body, leading to a relative lack of circulating blood even though no actual blood loss has occurred. Neurogenic shock can occur after a spinal injury or a traumatic brain injury, and poisoning can also be a cause.
How to recognize it?
- The general signs of shock listed above apply, but the skin is more likely to be warm and sweaty.
- In addition, the accident or discovery situation may give clues to a neurogenic shock.
- Numbness or loss of sensation (paralysis) in the arms and/or legs may be present.
- There may be visible head or spinal injuries.
What to do?
- Do not put them in the shock position! Do not change the person's position if they are conscious and breathing.
- If you must change the position because the person is unconscious or not breathing, make sure another helper stabilizes the head.
- Call emergency services as quickly as possible.
- Continuously check their level of consciousness and breathing.
Vasovagal syncope (often called fainting or passing out)
A special form counted under neurogenic shock is the vasovagal syncope. Syncope is the medical term for a short unconsciousness or fainting caused by a temporary reduction of blood flow to the brain. A vasovagal syncope is an exaggerated vagal response that leads to a brief loss of consciousness. The blood vessels temporarily dilate, blood pressure drops, and the return of blood to the heart is reduced. The person faints. Because they end up lying flat, blood flows back to the heart and they usually wake up again. This can happen after standing for a long time, but also as a reaction to emotional triggers like shock, fear, pain, or stress even strong emotions like joy can trigger it. Sometimes even the sight of a few drops of blood is enough. Vasovagal syncope is not a disease but an exaggerated reaction that doesn't cause long-term damage unless the person was injured when they fell. It should still be checked to make sure another cause is not behind the fainting.
How to recognize it?
Often the fainting is preceded by dizziness, nausea and paleness the person may seem absent.
What to do?
If the person is still standing, lay them down immediately and raise their legs (shock position). Put the person in this position even if they are already unconscious, and keep their airway open.
Cardiogenic shock (shock related to the heart)
Cardiogenic shock is caused by the heart's inability to pump enough blood. The heart can no longer pump sufficient blood into the circulation. Causes can include a heart attack, pulmonary embolism, myocarditis, a severely enlarged heart, or certain types of arrhythmias.
How to recognize it?
In addition to the general signs of shock, the cardiogenic shock shows these specific features:
On one hand, the person's complaints and behavior may point to a heart problem. They may report
- - a feeling of tightness or pressure in the chest
- - pain
- - shortness of breath
- - anxiety
- - a slow pulse possibly irregular
- - possibly swollen neck veins
What to do?
- Do not put them in the shock position! Sit them up and position them comfortably.
- Call emergency services as quickly as possible or make sure someone does.
- Shield the person from further agitation keep them calm and quiet.
- Loosen or remove tight clothing.
- Monitor the person continuously for consciousness and breathing.
- If an AED (defibrillator) is available, have it brought. These devices are made for use by laypeople and are very easy to use. Follow the device's instructions and voice prompts.
Hypovolemic shock (volume-loss shock)
Hypovolemic shock is caused by a lack of circulating fluid. This can be due to blood loss either internal bleeding (for example from a torn blood vessel or organ, gastrointestinal bleeding, or fractures of the pelvis or thigh) or external bleeding (heavily bleeding wounds) or by loss of water and electrolytes (vomiting, diarrhea, or dehydration) or plasma loss (burns, severe inflammation of the chest or abdomen, etc.).
How to recognize it?
- The general signs of shock apply.
- Visible external injuries with blood or plasma loss are present.
- The place where the person was found or the accident situation may indicate internal injuries.
- There may be a fracture of the pelvis or thigh.
What to do?
- Control bleeding
- Shock position, if there is no exception (injury to the chest or abdomen, spinal injury, pelvic or thigh fracture, head injury, difficulty breathing)
- Keep checking consciousness and breathing regularly
Allergic shock (anaphylactic shock)
Allergic shock is the most severe form of an allergic reaction. It can be caused by many allergens such as insect stings, foods, or medications. Anaphylactic shock is currently described as an acute pathological immune reaction to a chemical trigger that affects the whole body. It is divided into four grades.
How to recognize it?
- Grade 1: widespread hives, itching and/or redness, possibly dizziness, headache and anxiety
- Grade 2: in addition, a fast heartbeat and drop in blood pressure, often nausea and vomiting and mild breathing difficulty
- Grade 3: severe breathing difficulty (similar to an asthma attack), a strong drop in blood pressure, very fast heartbeat; an angioedema (formerly Quincke's edema) can occur swelling mainly around the eyelids, chin, cheeks, lips, tongue or genitals; hands and feet can swell a lot; airway involvement (especially the vocal cords) is dangerous and can lead to life-threatening breathing problems
- Grade 4: respiratory or cardiac arrest
What to do?
- Stop the possible cause if you can.
- Call emergency services as quickly as possible or make sure someone does.
- Calm and continuously monitor the person; keep the situation quiet.
- Shock position
- Keep them warm
- Continuously check consciousness and breathing.
- If the person vomits, help them as needed (do not force vomiting; assist by holding and preventing inhalation of vomit).
Septic shock
Septic shock can occur as a result of a blood infection (sepsis) or a similar condition for example an SIRS syndrome and requires immediate intensive medical treatment. People with weakened immune systems or those exposed to many pathogens are particularly at risk. Septic shock is diagnosed with laboratory tests.
Because septic shock occurs as a result of an existing blood infection (sepsis) and the patient is usually already under medical care, we omit further details here on "How to recognize?" and "What to do?".
Other types of shock
Other types of shock include endocrine forms caused by hormone deficiency or excess, toxic shock syndrome (TSS), hyperglycemic shock caused by very high blood sugar, and hypoglycemic shock caused by low glucose which is not a classic shock because it doesn't reflect an imbalance between oxygen supply and demand, but is triggered by lack of glucose.
Sources:
This article comes from BloodPressureDB – the leading app since 2011 that helps hundreds of thousands monitor their blood pressure every day.
Our content is based on carefully researched, evidence-based data and is continuously updated (as of 02/2026).
Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as in outpatient care, and has led BloodPressureDB's specialist editorial team since 2015. Thanks to her extensive additional qualifications as a paramedic, first responder and in various therapy and emergency areas, she provides solid, practical and reliably reviewed information.
Author Sabine Croci is a qualified medical assistant with many years of experience in internal medicine and cardiology practices as well as in outpatient care, and has led BloodPressureDB's specialist editorial team since 2015. Thanks to her extensive additional qualifications as a paramedic, first responder and in various therapy and emergency areas, she provides solid, practical and reliably reviewed information.
