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Active substance(s): NITROUS OXIDE

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Nitrous oxide
100%v/v medicinal gas,


Package leaflet:
information for the user

Nitrous oxide

Read all of this leaflet carefully before you start
using this medicine because it contains
important information for you.
• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your
doctor or pharmacist.
• This medicine has been prescribed for you only.
Do not pass it on to others. It may harm them,
even if their signs of illness are the same as yours.
• If you get any side effects, talk to your doctor or
pharmacist. This includes any possible side
effects not listed in this leaflet.
What is in this leaflet
1. What Nitrous oxide is and what it is used for
2. What you need to know before you use Nitrous
3. How to use Nitrous oxide
4. Possible side effects
5. How to store Nitrous oxide
6. Contents of the pack and other information
Nitrous oxide is an inhalation gas (intended for
breathing in). The active substance is nitrous
oxide, otherwise known as “laughing gas”. It
belongs to the group of general anaesthetics
(narcotic agents) and is administered by a doctor.
Nitrous oxide is used for short-term pain relief but
also as a component in anaesthesia for use in
adults and children from the age of 1 month:
• Nitrous oxide is used in combination with
oxygen as an anaesthetic, analgesic drug during
painful interventions of short duration, for example
after accidents, for the treatment of burns, dental
surgery, childbirth and ear, nose and throat
operations. In these cases, the composition of the
combination is always 50% nitrous oxide and
50% oxygen.
• Nitrous oxide mixed with oxygen is also used as
a basic anaesthetic in combination with other
In this case, the composition is variable but the
mixture always contains a minimum of 21%

The following information is intended for
healthcare professionals only:
Special precautions and conditions for
• Store gas cylinders between –20°C and +65°C.
• Store gas cylinders in a well-ventilated area
that is suitable for the storage of medicinal gases.
• Keep gas cylinders away from flammable
• Avoid all contact with oil, grease or similar
• Keep gas cylinders upright, except for those
gas cylinders with convex bases, which should
be stored lying down or in a crate.
• Protect gas cylinders from falling and other

Do not use Nitrous oxide
• If you inhale medical oxygen regularly or
• If there is a possibility of accumulation of air or
gas in the body. This may apply in cases of
untreated pneumothorax (“collapsed lung”),
vesicular pulmonary emphysema or
decompression sickness (“the bends”).
• If you suffer from impaired consciousness
(dizziness, confusion), so that you are unable to
cooperate adequately.
• If there is a sudden obstruction in the
gastrointestinal system.
• If there is a possibility of increased pressure in
the brain, characterised by severe headache,
blurred vision, increased cerebrospinal fluid
pressure, signs of neurological losses and
impaired consciousness.
• If there are facial injuries at the site where the
anaesthesia mask is placed on the face.
• After an injection of gas (e.g. SF6, C3F8) into
the eye this may lead to an increased volume in
the eye and possibly cause blindness. (The
doctor should not use Nitrous oxide until
sufficient time has passed.)
• If there is a vitamin B12 deficiency in early
Warnings and precautions
• If you have a vitamin B12 deficiency, such as
may occur in people with pernicious anaemia
(malignant form of anaemia) or Crohn’s disease
(chronic enteric disease), or in vegetarians.
• If you have impaired heart function (if your
heart does not perform adequately).
• If you have seriously low blood pressure as a
result of shock or heart failure.
• If you have sickle cell anaemia (a specific
blood disease in which the red blood cells have
an abnormal shape).
• If analgesia involving opium is given in
childbirth (the combination of this type of drug
with Nitrous oxide may cause loss of
• After an injection into the eye (with another
agent), sufficient time must have passed before
Nitrous oxide is given because otherwise there
is a risk of eye problems (including blindness).
• When benzodiazepines are used at the same
time (a specific group of drugs with
tranquillising, soporific and/or muscle-relaxing
properties) because loss of consciousness may
• If you are being treated with bleomycin
(a medicine used in the treatment of cancer).
Please ask your doctor if one of the warnings
above applies to you or if it has done so in the
Other medicines and Nitrous oxide
Tell your doctor or pharmacist if you are taking,
have recently taken or might take any other
NOTE: the following statements may also apply
to the use of medicines prior to or for some time
after using Nitrous oxide.

• Narcotic drugs enhance the action of Nitrous
• Medicines containing morphine enhance the
analgesic and sedative effects of Nitrous oxide.
• Benzodiazepines and barbiturates (a specific
group of drugs with tranquillising, soporific
and/or muscle-relaxing properties) enhance the
effect of Nitrous oxide and the combination of
these drugs with Nitrous oxide may result in
loss of consciousness.
• The action of certain muscle relaxants (such
as pancuronium, vecuronium) is enhanced by
Nitrous oxide.
• The damage caused by sodium nitroprusside
(a drug to treat high blood pressure) and
methotrexate (a drug used in the treatment of
cancer) is increased because the action of
vitamin B12 is overridden by Nitrous oxide.
• The damage caused by bleomycin (a drug
used in the treatment of cancer) to the lungs
may be increased with increased administration
of oxygen (such as occurs with treatment with
Nitrous oxide).
Nitrous oxide with food and drink
If Nitrous oxide is used as a component of an
anaesthetic, nothing may be eaten or drunk
after midnight on the night before the treatment
because Nitrous oxide may cause nausea or
vomiting (see section 4 “Possible side effects”).
Pregnancy, breast-feeding and fertility
Ask your doctor or pharmacist before taking
any medicine.
Limited data on the short-term use of Nitrous
oxide during pregnancy indicate no increased
risk of congenital malformations. In rare cases,
Nitrous oxide may cause breathing problems in
newborns. Nitrous oxide may be used during
pregnancy only if it is strictly necessary.
Long-term or frequent use must be avoided.
It is unknown whether Nitrous oxide is excreted
in human milk. It is not necessary to
discontinue breast-feeding after short-term
Driving and using machines
• Do not drive or use any tools or machines for
24 hours after using Nitrous oxide in
combination with anaesthetic drugs because
Nitrous oxide has a major effect on the ability to
drive and operate machines.
• Be careful after short-term administration of
Nitrous oxide for pain relief. You may not drive
or use machines until any side effects have
disappeared and you are once more as alert as
before being given the treatment.

shocks by fixing them in position or storing them
in a crate.
• Gas cylinders containing a different type of
gas or containing a different composition must
be stored separately.
• Store full and empty gas cylinders separately.
• Do not store gas cylinders in the vicinity of a
heat source.
• Store gas cylinders covered and protected
from atmospheric influences.
• The valves of gas cylinders for nitrous oxide
are fitted with a rupture disc to prevent the
cylinder bursting if pressure inside the cylinder
becomes too high. The rupture disc may fail if
the temperature is too high. This will release the
entire contents of the cylinder.

In this event, do not enter the storage area and
ventilate the area well until it is cleared for use by
an expert.
Instructions for use, processing and disposal
Follow the instructions of your supplier,
• Nitrous oxide may be administered only once
suitable pressure and output regulation has
been created between the cylinder and the
• Before the valve on the cylinder is opened, the
cylinder must be placed in a vertical position
and kept in a vertical position during

For inhalation use.
Nitrous oxide is administered by a doctor who will
also establish the correct dose.
For short-term use for pain relief
When used for pain relief, Nitrous oxide is only
given in combination with the same proportion of
oxygen (50% nitrous oxide and 50% oxygen).
The maximum period of administration does not
exceed 1 hour continuously per day. This
treatment may not be repeated for more than
15 consecutive days.
For use in combination with anaesthetic drugs
When used in combination with anaesthetic
drugs, Nitrous oxide is only given after being
mixed with a minimum of 21% oxygen. Nitrous
oxide alone is unable to cause anaesthesia.
Combination of anaesthetic drugs with Nitrous
oxide means that all the agents are taken up more
rapidly and smaller amounts of the other
anaesthetic drugs are required. The effect can
generally be noticed within 2 to 5 minutes.
Instructions for the use of Nitrous oxide
Nitrous oxide is only given after being mixed with
a minimum of 21% oxygen and using equipment
designed for this purpose and utilising a wellfitting mask.
Nitrous oxide is always given by a doctor.
It is administered in well-ventilated areas, using
gas scavenging with a double mask, for example,
to prevent exhaled Nitrous oxide entering the
ambient air.
If you use more Nitrous oxide than you should
The consequences of Nitrous oxide overdose
result in acute oxygen shortage. In the event of an
overdose, administration of Nitrous oxide must be
stopped immediately and you will need to be
ventilated with air or oxygen until the oxygen
concentration in your blood returns to normal.
If you stop using Nitrous oxide
After you stop using Nitrous oxide and medical
oxygen an oxygen shortage may develop.
To prevent this from occurring, you can be
temporarily ventilated with 100% oxygen.
If you have any further questions on the use of this
medicine, ask your doctor or pharmacist.
Like all medicines, this medicine can cause side
effects, although not everybody gets them.
The side effects below have been classified by
organ system. Few accurate data are known
regarding the frequency of the side effects but
side effects occur more often with a higher
dosage and/or longer period of administration.
Nausea and vomiting are the most common side
Blood and lymphatic system disorders:
Severe disruptions of the complete blood count
(megaloblastic anaemia, granulocytopenia) have
been observed after administration for longer than
24 hours. It is assumed that a single exposure for
up to 6 hours involves no risk.
Nervous system disorders:
Decreased circulation in the brain and decreased
glucose consumption by the brain.
Psychedelic effects may occur even if no other
anaesthetic drug is used.
• Administration of nitrous oxide must take place
at the same time as administration of oxygen by
means of a secure mixer; the pressure of nitrous
oxide in the lines must always be lower than the
oxygen pressure.
• If a variable mixer is used, monitoring with an
oxygen analyser is recommended.
• The gas cylinder may not be used if it has
sustained visible damage or if it is suspected of
being damaged or of having been exposed to
extreme temperatures.
• All contact with oil, grease or similar substances
must be avoided.
• Only apparatus that is suitable for the specific
type of gas cylinder and gas may be used.

Neurological effects: spinal cord disorders,
neuropathy, epilepsy, increased pressure in the
skull, symptoms of paralysis in both legs with
muscle cramps.
Psychiatric disorders: psychosis (serious mental
illness in which control over one’s own
behaviour and actions is impaired), confusion
and headache, but also effects reducing anxiety
and improving mood.
Temperature disorders:
Very severe decrease and/or increase in body
Eye disorders:
Slowed eye movements.
Temporary increase in pressure and/or volume
of the eye if Nitrous oxide is used after an
injection of a gasforming drug into the eye.
Ear and labyrinth disorders:
Temporary increase in pressure and/or volume
of the enclosed cavities in the middle ear.
Cardiac and vascular disorders
Cardiac arrhythmia, heart failure, raised blood
pressure in the lungs and low blood pressure in
the body.
Respiratory, thoracic and mediastinal disorders:
Respiratory depression, air in the chest cavity,
subcutaneous emphysema and symptoms
comparable to a respiratory infection.
Oxygen shortage for a few minutes after ending
the administration of Nitrous oxide.
Gastrointestinal disorders
Nausea and regularly, vomiting.
Temporary increase of pressure and/or volume
in the intestines and abdominal cavity.
Hepatobiliary and pancreatic disorders:
Jaundice and increase in liver enzyme
Reporting of side effects
If you get any side effects, talk to your doctor or
pharmacist. This includes any possible side
effects not listed in this leaflet. You can also
report side effects directly via the Yellow Card
Scheme at:
By reporting side effects you can help provide
more information on the safety of this medicine.
Nitrous oxide is stored and kept by qualified
staff in accordance with the instructions
provided by the manufacturer and the relevant
Do not use this medicine after the expiry date
which is stated on the label after {Exp.}.
What Nitrous oxide contains
• The active substance is nitrous oxide
(dinitrogen monoxide).
• Nitrous oxide contains no other ingredients.
What Nitrous oxide looks like and contents of
the pack
• Nitrous oxide is an inhalation gas (intended for
breathing in) and is packed in liquid form in
pressurised gas cylinders.

• No tongs, forceps or other instruments may be
used to open or close the cylinder valve so as to
avoid damaging it.
• The packaging type may not be changed.
• In the event of a leak, the gas cylinder valve
must be closed immediately if this can be
achieved safely. If it is not possible to close the
valve, the gas cylinder must be taken to a safe
place out of doors and allowed to run empty.
• Close the valves of empty gas cylinders.
• Siphoning off compressed gas is not allowed.
• Installations to be used, with central storage,
distribution networks, pipeline system, terminal
units and connections must comply with the
relevant applicable legislation.

The cylinders are colour-coded : body is pure
white (RAL 9010) and the shoulder is gentian blue
(RAL 5010).
• The table below gives the content of the various
gas cylinders (in litres) and the associated number
of kilograms of nitrous oxide gas at a temperature
of 15°C.
in litres (x)

Amount of
kg nitrous
oxide gas

in litres (x)

Amount of
kg nitrous
oxide gas



























Not all pack sizes may be marketed.

Marketing authorisation holder and
Marketing Authorisation holder
SOL S.p.A.
via Borgazzi 27, 20900 Monza, Italy
Swaardvenstraat 11
5048 AV Tilburg, The Netherlands
BTG Sprl
Zoning Ouest 15, 7860 Lessines, Belgium
SOL S.p.A.
via Acquaviva 4, 26100 Cremona, Italy
SOL Hellas S.A.
Thesi Paxi Patima Stefanis
19200 Kamari Boiotias, Greece
SOL France S.A.S.
ZI des Béthunes, 8 Rue du Compas
95310 Saint Ouen L’Aumone, France
This medicinal product is authorised in the
Member States of the EEA under the following
Belgium: Protoxyde d’azote Médicinal SOL
100% v/v, gaz médicinal liquéfié
Bulgaria: Медицински диазотен оксид SOL
100% v/v, втечнен медицински газ
Luxemburg: Protoxyde d’azote Médicinal SOL
100% v/v, gaz médicinal liquéfié
Slovenia: Medicinski didušikov oksid SOL 100%
medicinski plin, utekočinjen
The Netherlands: Distikstofoxide Medicinaal
SOL, medicinaal gas, vloeibaar gemaakt
100% v/v
UK: Nitrous oxide 100%v/v medicinal gas,
This leaflet was last revised in 06/2015

• Nitrous oxide may cause glowing or
smouldering materials to ignite suddenly; it is
therefore prohibited to smoke or have an open
flame in the vicinity of a gas cylinder.
• Nitrous oxide is a nontoxic, non-flammable gas,
heavier than air and will feed a fire. It may form
explosive mixtures in combination with flammable
anaesthetic gases or vapours, even in the
absence of oxygen.
• Return the cylinders to the supplier once they
are empty.

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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.