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Serinox

About the medicine

How to use Serinox

PATIENT INFORMATION LEAFLET

Leaflet accompanying the packaging: information for the user

Serynox, 50% + 50%, compressed medical gas

Nitrous oxide + oxygen

Read the leaflet carefully before using the medicine, as it contains important information for the patient.

  • Keep this leaflet, you may need to read it again.
  • If you have any further questions, ask your doctor, pharmacist, or nurse.
  • If you experience any side effects, including any not listed in this leaflet, tell your doctor, pharmacist, or nurse. See section 4.

Table of contents of the leaflet

  • 1. What is Serynox and what is it used for
  • 2. Important information before using Serynox
  • 3. How to use Serynox
  • 4. Possible side effects
  • 5. How to store Serynox
  • 6. Contents of the packaging and other information

1. What is Serynox and what is it used for

  • Serynox contains a mixture of 2 medical gases:
  • 50% nitrous oxide (medical "laughing gas"),
  • 50% oxygen (medical oxygen).

Its use involves inhaling the gas mixture. At this concentration, Serynox does not have any narcotic (anesthetic) effect. Serynox belongs to the class of combination products containing nitrous oxide. Serynox can be used in adults, adolescents, and children over 1 month of age.

The action of Serynox is to reduce the sensation of pain and cause a feeling of relaxation during:

  • short-term painful procedures or treatment of mild to moderate pain and sedation during dental procedures, when rapid onset and offset of analgesic action are desired.

2. Important information before using Serynox

When not to use Serynox

During inhalation of Serynox, gas bubbles and body cavities filled with gas may increase in volume and cause serious complications. Therefore, Serynox should not be used in the following cases:

  • head injury,
  • facial or jaw injuries,
  • air accumulation between the lung and the chest wall (pneumothorax),
  • pulmonary bullous disease causing breathing problems (severe emphysema),
  • formation of air bubbles in the bloodstream (air embolism),
  • deep diving with a risk of decompression sickness,
  • brain X-ray examination,
  • middle ear, inner ear, or sinus surgery,
  • presence of air in the abdominal cavity, causing severe discomfort in the abdominal cavity,
  • receipt of spinal anesthesia to eliminate pain from the waist down (epidural anesthesia), during which air was injected.

Warnings and precautions

Before starting treatment with Serynox, discuss it with your doctor. Serynox should be administered by trained personnel. However, self-administration under medical supervision is preferred to assess the patient's level of consciousness. The patient should NEVER operate the cylinder containing Serynox. Rooms where Serynox is used should be well-ventilated and (or) equipped with an exhaust system to maintain the lowest possible concentration of nitrous oxide in the surrounding air. The patient should breathe normally during Serynox inhalation. It is not recommended for use in newborns. If Serynox was administered to the mother during childbirth, newborns should be monitored for adverse reactions, especially respiratory depression. Prolonged or repeated administration of Serynox may lead to abuse and dependence. Repeated or prolonged administration of Serynox may cause inactivation of vitamin B12 in the body. The doctor may decide to prescribe vitamin B12 to the patient. In the following situations, you should consult a doctor, as there is a risk of vitamin B12 deficiency:

If the patient or child suffers from acute ear inflammation, they should inform the doctor.

Serynox and other medicines

Tell your doctor or pharmacist about all medicines you are taking, or have recently taken, and about medicines you plan to take. Tell your doctor if:

  • you have received an eye gas injection during eye surgery. There is a risk of postoperative complications if the pressure in the eye is too high.
  • you are taking medicines that act on the central nervous system (such as morphine derivatives, benzodiazepines, and other psychotropic medicinal products). They may enhance sedative effects.
  • you are taking vitamin B12 and folic acid, as Serynox may inactivate vitamin B12.

Serynox may increase the toxicity of methotrexate, disrupting folate metabolism. The toxic effect on the lungs associated with active substances such as bleomycin, amiodarone, nitrofurantoin, and similar antibiotics may be increased as a result of inhaling higher concentrations of oxygen.

Pregnancy, breastfeeding, and fertility

If you are pregnant or breastfeeding, think you may be pregnant, or plan to have a child, consult your doctor or pharmacist before using this medicine. Serynox may be used during pregnancy if clinically necessary. If used during the perinatal period, the newborn should be monitored for adverse reactions. However, it is not necessary to discontinue breastfeeding after short-term administration of Serynox.

Driving and using machines

Serynox affects perception and movement (cognitive and psychomotor functions). After administration of Serynox, the patient will be observed until all effects have subsided and until the same level of alertness as before administration is regained. Driving and operating machinery are activities that require psychomotor functions and are not recommended after nitrous oxide administration for a reasonable period after exposure.

3. How to use Serynox

Dosage Only personnel with knowledge of this form of the medicine are authorized to administer Serynox. The doctor will explain how to use Serynox, how it works, and what effects it causes. In some procedures, the patient will hold the device used to administer the gas, allowing the patient to self-dose the gas. During Serynox use, the patient and administration will be monitored to ensure safe administration. If verbal contact with the patient is lost, Serynox administration should not be continued. Maximum analgesic effect is achieved after at least 3 minutes. Method of administration Serynox is intended for inhalation. Serynox is a mixture of two medical gases that the patient inhales and is administered through a suitable device via a mask placed on the face. During Serynox inhalation, breathe normally. After finishing Serynox use, remove the mask, rest, and wait until you regain full consciousness. Duration of treatment The use of Serynox depends on the duration of the procedure and should not exceed 60 minutes of inhalation per day. Repeated administration of Serynox should not last longer than 15 days.

Using a higher dose of Serynox than recommended

There is a very small likelihood that the patient will receive too much gas, as the patient controls how much gas they inhale through the mask and is closely monitored. If the patient breathes faster than usual and thus takes in more nitrous oxide than during normal breathing, they may feel very tired and have a feeling of losing contact with their surroundings. In such a situation, immediately inform medical personnel and stop administration. If the patient's skin turns blue (cyanosis) during Serynox use, medical personnel will immediately stop treatment. If this does not lead to rapid resolution of cyanosis, the patient will be ventilated using a manual resuscitator bag filled with air or oxygen.

Stopping Serynox use

The analgesic effect subsides immediately after stopping Serynox administration without any irreversible effects. If you have any further questions about using this medicine, ask your doctor or pharmacist.

4. Possible side effects

Like all medicines, Serynox can cause side effects, although not everybody gets them. The following side effects may occur during treatment and usually subside within a few minutes after stopping the gas mixture inhalation:

Common: may affect up to 1 in 10 people

  • dizziness,
  • giddiness,
  • nausea,
  • vomiting.

Uncommon: may affect up to 1 in 100 people

  • tingling (paresthesia),
  • increased sedation (drowsiness),
  • hallucinations,
  • anxiety,
  • agitation,
  • euphoria,
  • dreams.

Unknown: frequency cannot be estimated from the available data

  • headache,
  • seizures,
  • increased intracranial pressure (see section 2 - When not to use Serynox),
  • ear pain,
  • psychosis,
  • confusion,
  • disorientation,
  • respiratory depression (in newborns during childbirth),
  • severe vision disorders (caused by increased gas volume in the eyeball, see section 2 - When not to use Serynox).

After prolonged or repeated exposure to Serynox

Unknown: frequency cannot be estimated from the available data

After rapid breathing during inhalation (hyperventilation), abnormal movements may occur. Neurological disorders, such as spinal cord diseases (myeloneuropathies). Decreased red blood cell count with a concurrent decrease in white blood cell count (megaloblastic anemia with leukopenia). Abuse and dependence. Vitamin B12 deficiency (see section 2 - When not to use Serynox, Warnings and precautions, Serynox and other medicines).

Reporting side effects

If you experience any side effects, including any not listed in this leaflet, tell your doctor, pharmacist, or nurse. Side effects can be reported directly to the Department of Adverse Reaction Monitoring of Medicinal Products, Medical Devices, and Biocidal Products

Al. Jerozolimskie 181C

PL-02 222 Warsaw

Tel.: + 48 22 49 21 301

Fax: + 48 22 49 21 309

Website: https://smz.ezdrowie.gov.pl

Side effects can also be reported to the marketing authorization holder. By reporting side effects, you can help provide more information on the safety of this medicine.

5. How to store Serynox

Keep the medicine out of the sight and reach of children. Do not use this medicine after the expiry date stated on the gas cylinder after the EXP. abbreviation.

Storing gas cylinders

Store gas cylinders as follows: Securely closed gas cylinders should be stored in a VERTICAL POSITION (full cylinders in a designated gas storage area, full, used cylinders, full cylinders for transport within medical facilities, and in vehicles, stored empty cylinders). There are no special recommendations for storing the medicine at a certain temperature. Different types of medical gases must be separated from each other. Full and empty gas cylinders must be stored separately.

Storing full cylinders in a designated gas cylinder storage area

Full cylinders must be stored in a VERTICAL POSITION in a clean, well-ventilated area, where there are no flammable materials, and which is protected from weather conditions. The room must be reserved for storing medical gases and closed. Empty and full cylinders should be stored separately. Full cylinders should be protected from tipping and dropping, and kept away from heat sources, ignition, and flammable substances. They should also be protected from weather conditions, especially cold. After delivery by the manufacturer, the cylinders must have intact seals that allow easy verification of their integrity.

Transporting full cylinders

In medical facilities, full cylinders must be securely closed in a VERTICAL POSITION, using suitable means (hand trucks with chains, handles, or rings) for transport, to protect them from shocks and falls. During transport in vehicles, full cylinders must be securely closed in a VERTICAL POSITION. You should instruct rescue services that the cylinders must be protected from cold in vehicles and during outdoor use. Pay particular attention to the pressure regulator connection, in the case of cylinders with residual pressure valves, to avoid accidental damage.

Storing empty cylinders

Empty cylinders should be stored securely closed in a VERTICAL POSITION. Valves must be closed.

6. Contents of the packaging and other information

What Serynox contains

  • The active substances of Serynox are: 50% nitrous oxide and 50% oxygen
  • Serynox does not contain any other ingredients.

What Serynox looks like and contents of the packaging

Serynox is a colorless compressed medical gas. 2-liter, 5-liter, 10-liter, 15-liter, and 20-liter aluminum or steel gas cylinders (identified by a blue and white cap and a white body) filled under pressure of 170 bar, equipped with a residual pressure valve or valves with an integrated pressure regulator, both with a special outlet connection. Not all pack sizes may be marketed.

Water capacity of the container [l]Equivalent of the gas mixture of nitrous oxide + oxygen in m³ at a pressure of 1 bar and a temperature of 15°C
20.59
51.49
102.97
154.46
205.95

Marketing authorization holder and manufacturer

Marketing authorization holder

Messer Polska Sp. z o.o.

ul. Maciejkowicka 30

41-503 Chorzów

Poland

Manufacturer

MESSER FRANCE

ZI Lafayette, 35 rue de l'Europe

38790 Saint-Georges-d'Espéranche

France

This medicinal product is authorized in the Member States of the European Economic Area under the following names:

Austria, Germany:Serynox 50% / 50% Gas zur medizinischen Anwendung, druckverdichtet

Belgium:Placynox 50% / 50% v/v medicinaal gas, samengeperst / gaz médicinal comprimé

Croatia:Serynox 50%/50% V/V medicinski plin, stlačen

Czech Republic:Serynox

Estonia, Latvia, Lithuania:Serynox

France:Placynox 50% / 50% gaz médicinal comprimé

Poland:Serynox

Romania:Serynox 50% / 50% Gaz medicinal comprimat

Slovenia:Serynox 50 %/50 % V/V medicinski plin, stisnjeni

Slovakia:Serynox 50% / 50% stlačený medicinálny plyn

Spain:Serynox 50% / 50% gas comprimido medicinal

Date of last revision of the leaflet: 2024.10

------------------------------------------------------------------------------------------------------------------------

Information intended for healthcare professionals only

Serynox cylinders must be used exclusively for medical purposes.

Preparing full cylinders 48 hours before use

The mixture is unstable at temperatures below -5°C. Further cooling may lead to condensation of part of the nitrous oxide, causing the administration of an uneven gas mixture containing too much oxygen (a mixture with reduced analgesic effect) at the beginning of treatment and too much nitrous oxide (a hypoxic mixture) at the end of treatment. For this reason, before the first use, full cylinders must be placed in a HORIZONTAL POSITION for at least 48 hours at a temperature above +10°C, in a buffer zone in the pharmacy and (or) on the ward where the medicine is administered. Cylinders should be placed in a location where they are not at risk of tipping, heat sources, or ignition and flammable materials. The cylinder valves should be closed. Before use, place the gas cylinder in a VERTICAL POSITION. Rooms where Serynox is frequently used must be equipped with an appropriate exhaust system for waste gases or ventilation. Different types of medical gases must be separated from each other. Full and empty gas cylinders must be stored separately. Never use oils or greases, even in case of difficulty turning the cylinder valve or connecting the regulator. Valves and other equipment should be handled with clean, grease-free (hand cream, etc.) hands. Close the valve of the device in case of fire or when not in use. In case of fire risk, move the gas cylinder to a safe place. Use only standard equipment intended for a 50% N2O + 50% O2 gas mixture. Ensure that the cylinders are sealed before they are handed over for the first use. Smoking and using open fire is strictly prohibited in rooms where Serynox treatment is performed. During use, the cylinder must be secured on a suitable bracket. After use, the cylinder valve must be closed manually. Release the pressure from the regulator or connection. Do not dispose of empty gas cylinders. Empty gas cylinders will be collected by the supplier.

  • Country of registration
  • Active substance
  • Prescription required
    Yes
  • Manufacturer
  • Importer
    Messer France

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