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Hospital Particular Alvor

Superior a 1H30

Atendimento Urgente

Hospital Particular Gambelas


Atendimento Urgente



Hospital Particular da Madeira


Atendimento Urgente



Madeira Medical Center


Atendimento Urgente

Sedation without needles and of short duration

HPA Magazine 9

Nitrous oxide, also known as “laughing gas” due to its relaxing effect, has been used for decades in the United States and England. It has an analgesic effect, and reduces the sensation of pain.
Discovered in 1771 by scientist Joseph Priestly, it only began to be used clinically in 1844, when American dentist Horace Wells understood that nitrous oxide, “laughing gas”, popularly used in fairs to cause uncontrollable laughter, had anaesthetic properties. Seated in the chair in his own practice, he inhaled nitrous oxide and ordered a colleague to extract a wisdom tooth. 
The procedure did not hurt at all! From 1960, nitrous oxide began to be widely used as a pre-mixture with 50% oxygen.


This analgesic is always pre-mixed with 50% oxygen. As it is non-invasive, no needles are used to administer it and it is easy and fast to use, economising time for the patient and the health professionals. All that is necessary is for the person to breathe through a mask during the procedure. The first effects are felt after just 5 or 6 inhalations and its maximum effect is reached in 3 minutes. When it ceases to be administered, recuperation happens quickly, within the next 3 to 5 minutes.
This type of inhalation analgesic has an adverse risk rate of less than 5% and can be used in combination with other types of analgesia. 
Nitrous oxide is very safe and has few contraindications. There are only a few cases in which it should be avoided: chronic obstructive pulmonary disease, the first trimester of pregnancy and with regular medication of anxiolyticand/or antidepressants.

Nitrogen protoxide has little or no side effects, it can therefore be administered to people of all ages. Due to its high success rate and a broad spectrum of clinical action, it is used worldwide in medical areas such as in Emergency Medicine, Dental Medicine, Orthopedics and in Anesthesia during Labor and Childbirth.

Always give your health professionals your clinical record and tell them what medication you are taking.