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University Medicine Cluster

Common Conditions:




High Blood Pressure


High Cholesterol

Chronic Obstructive Pulmonary Disease

Lung Cancer


Obsessive Compulsive Disorder




When to seek medical advice

Key circumstances may lead you to talk to your doctor about presyncope/syncope:

•    Frequent attacks

•    No clear trigger for attacks

•    Chest pain or rapid heart rate/pounding heart just before the attack starts

•    Double vision, slurred speech, difficulty swallowing, numbness around the mouth, weakness of one side of the body before or after the attack

•    Severe headache before or after the attacks

•    Fits are seen when the person is unconscious eg abnormal limb jerks, foaming at the mouth



Syncope is more commonly known as a fainting spell. It is due to transient (short-lasting) reduced flow of blood to all parts of the brain. If the person has all the symptoms (as described below) except the loss of consciousness, it is called “pre-syncope” – many patients have symptoms of pre-syncope before they go onto to develop syncope (loss of consciousness) a few seconds or minutes later.



The symptoms of syncope are usually quite typical and easily recognized. If there is more than 1 attack, the symptoms tend to be similar to the first attack. It is important to remember that some of these symptoms may similar to those seen in other conditions affecting the brain. This potential confusion makes identifying the settings in which the symptoms occur very important in recognizing this disorder.

The common recognized symptoms tend to occur as a sequence
•    Feeling unwell or light headed
•    Sounds and images appear distant and unfocused
•    Sweating and/or palpitations
•    Vision slowly darkens
•    Body feels weak all over
•    Gradual loss of consciousness(syncope)
•    Fall to the ground

These symptoms usually develop over many seconds to minutes.

The person may look unwell and pale. When unconscious, the eyes are usually closed, breathing is normal, the body is soft. There are usually no abnormal movements (eg jerks), accidental wetting by urine, tongue biting, foaming at the mouth.

Attacks usually last a few minutes, and the person regains full consciousness without any other symptoms except feeling a bit weak for some minutes before returning to normal.

There are a number of well-known triggers of syncope/presyncope. These include:
•    Prolonged standing eg on a bus/MRT, on parade
•    Severe pain eg abdominal cramps, limb injury
•    Seeing something frightening eg blood
•    After straining eg trying to pass urine especially in older men with prostate problems
•    After suddenly changing posture eg getting up from sitting to standing , or lying to standing, especially in those taking medications for high blood pressure, prostate problems, or those with diabetes with complications affecting the nerves
•    Those with bleeding, anemia(low red blood cell count), dehydration (eg having bad diarrhoea), excessive tiredness, general ill-health

Syncope fact

•    Syncope has many causes
•    Several studies show that after reviewing the history, examination findings, and electrocardiogram(ECG), the doctor can establish the underlying diagnosis in about 50 percent of patients
•    Often, the cause is not found, despite exhaustive investigations


Treatment and drugs

Treatment generally involves avoiding the things that trigger the presyncope/syncope ie prevention is the key. Drug treatment is seldom needed.

Simple first aid measures include
•    Laying the person down
•    Loosening tight clothing, belt, tie
•    Elevating the legs
•    Allowing adequate ventilation
•    Do NOT place objects in the mouth, poke the fingers with needles, slap the person to awaken him/her


Appointment and Enquiry

Most people with syncope should first consult their family physician. The doctor will refer to the specialist if it is needed