Fentanyl is an opioid synthetic analgesic. In its chemical structure, such a substance is similar to promedol. With a single use, it has a very strong, but short-term effect.
In surgery using local anesthesia, fentanyl can be used as an additional pain medication (usually in combination with some antipsychotic).
Medicines based on this substance are prescribed to patients with the aim of relieving acute pain during myocardial infarction, pulmonary infarction, angina pectoris, as well as hepatic and renal colic. Typically, in such conditions, fentanyl preparations are administered intravenously or intramuscularly.
However, for certain diseases, drugs with the aforementioned component are used externally. One of these local anesthetics is fentanyl patch. Side effects of this drug, indications for its use, analogues and other information are discussed below.
Form, packaging and composition
Fentanyl patch is a transdermal therapeutic system. What does an analgesic for external use look like? This is a translucent rectangular patch with rounded edges, having a removable transparent protective film (divided into 2 parts by a sinusoidal incision), exceeding the size of the patch itself.
Fentanyl agent is packaged in a heat sealable bag of paper, aluminum and polyacrylonitrile. In a cardboard box are five packages, as well as detailed instructions for use.
The composition of the drug under consideration includes such an active component as fentanyl. As for the protective removable layer, it is a polyester film with a fluorine-containing polymer coating.
How does it work?
The transdermal fentanyl patch is a topical preparation that provides systemic delivery of the active substance over a period of 72 hours.
Fentanyl is an opioid analgesic related to the opioid µ receptors of the central nervous system, peripheral tissues, and spinal cord. This substance is able to increase the activity of the antinociceptive system and increase the threshold of pain sensitivity. Thus, the drug on the basis of fentanyl has a sedative and analgesic effect.
Other properties of the substance
Despite the fact that fentanyl patch is applied externally, it should be borne in mind that the active substance of this drug is able to exert a depressing effect on the respiratory center, slow down the heart rate, stimulate the vomiting center and n.vagus centers, and increase the tone of smooth muscles (mainly bile duct muscles and sphincters ), improve the absorption of water from the digestive tract. Also, this component can reduce blood pressure, renal blood flow and intestinal motility. In blood plasma, fentanyl increases the concentration of lipase and amylase, reduces the concentration of growth hormone, ACTH, catecholamines, cortisol and prolactin.
It can not be said that the substance in question causes euphoria and the onset of sleep (in connection with the elimination of the pain syndrome).
The rate of development of tolerance to analgesic effects and drug dependence has individual differences. Compared with other opioid analgesics, fentanyl is much less likely to provoke histamine reactions.
What pharmacokinetic features are inherent in the anesthetic fentanyl patch? The minimum effective analgesic concentration in the blood in people who have not previously used opioid drugs is approximately 0.3-1.5 ng / ml.
After the first use of the medication, the concentration of its active substance in the plasma increases gradually and evens out between 12 and 24 hours. The result is stored for the next 72 hours.
According to the instructions, the concentration of fentanyl in the patient's blood is proportional to the size of the patch. The absorption of this substance may vary depending on the place of application. In the course of studies, it was noted that reduced absorption of fentanyl is noted when the patch is placed on the chest (compared to the upper back and arm).
Experts report that fentanyl is able to pass through the placenta, the BBB and into breast milk. This component binds to plasma proteins by 84%. It also has linear kinetics of biological transformation and is metabolized in the liver by CYP3A4 enzymes.
After removal of the patch in question, its serum concentrations decrease gradually. The half-life of fentanyl after application is 17 hours. This substance is excreted along with urine and bile.
Special Clinical Cases
Impaired functioning of the kidneys and liver can increase the serum concentration of fentanyl.
In the elderly, as well as debilitated or depleted patients, the use of the drug may cause a decrease in the clearance of fentanyl. In this case, a longer half-life of the active substance is possible.
What is fentanyl patch used for? Indications for use of this tool are chronic pain sensations of a strong and moderate degree, requiring analgesics with analgesics (opioid). Usually such an external drug is prescribed for:
- oncological pain
- pain syndromes of non-oncological origin, requiring multiple analgesic analgesics (for example, with neuropathic pain, arthritis and arthrosis, phantom pain after amputation of the limbs).
Prohibitions to use
Before using fentanyl patch, the indications for use of which were listed above, it is imperative to familiarize yourself with the contraindications. These include the following conditions:
- severe damage to the central nervous system,
- acute respiratory depression
- toxic dyspepsia
- irritated, damaged or irradiated skin in the area of the intended application,
- diarrhea with pseudomembranous colitis due to the intake of lincosamides, cephalosporins and penicillins,
- minor age
- acute postoperative pain
- concomitant use of MAO inhibitors, as well as the use of the drug for two weeks after their withdrawal,
- high sensitivity to the active substance or auxiliary components of the drug.
With particular care, the medication in question is used for chronic lung diseases, brain tumors, intracranial hypertension, arterial hypotension, traumatic brain injury, gallstone disease, bradyarrhythmias, drug dependence, liver / kidney failure, hypothyroidism, renal / hepatic colic, surgical diseases of the abdominal cavity acute (prior to diagnosis), alcoholism, acute severe condition, BPH, urethral strictures, hyperthermia, suicidal th inclinations, concomitant use of corticosteroids, insulin, antihypertensive agents, as well as in the elderly, the weak and malnourished patients.
Fentanyl transdermal patches release their active component within 72 hours. At the same time, its release rate is from 12.5 to 100 μg / h.
The required therapeutic dosage of fentanyl is selected individually and should be evaluated after each use of the patch.
The choice of the initial dose of the drug depends on the level of administration of opioid analgesics in the previous time, taking into account the likely development of tolerance, severity of the disease, concomitant treatment and the general condition of the patient.
In that case, if the nature of the patient’s reaction to opioids is not fully understood, the initial dosage should not be higher than 25 μg / h.
How to switch from other opioid analgesics?
Use an anesthetic patch (fentanyl) for oncology after other oral or parenteral opioid analgesics should be used with extreme caution. It should be remembered that the initial dose of drugs with fentanyl is calculated in a special way. For accurate dosing, consult a specialist.
Assessment of the maximum analgesic effect of the drug in question can be carried out only a day after the application. This limitation is associated with a gradual increase in the concentration of fentanyl in the blood in the first 24 hours.
According to the instructions for use, the fentanyl patch must be replaced with a new one after 72 hours. The dosage of the drug is selected individually until the desired level of pain relief is achieved. In the event that, after 48-72 hours after application, a noticeable decrease in the analgesic effect is observed, then the patch is replaced after two days.
Method of application of the patch Fentanyl
The medication in question is used transdermally. The patch is placed on a flat surface of unirradiated and intact skin (on the trunk or shoulder). For the place of application, it is advisable to choose the areas with the least amount of hair. Before placing the patch on the hairline of the body, they should be cut off (but not shaved!).
In the event that the skin area needs to be washed before applying the drug, then it is better to do it with ordinary water (without using soap, oil, lotions, alcohol or other means that can cause irritation or change the properties of the skin). Before application, the covers should be completely dry.
Due to the fact that the fentanyl patch, the contraindications of which were listed above, has a protective waterproof outer film, it can not be removed before a short shower.
The preparation in question should be applied immediately after removal from the packaging bag. After removing the protective film, the transdermal patch is firmly pressed to the place of application and kept in this state for about 30 seconds. After this, make sure that the patch adheres strongly to the skin, including along the edges. If required, then resort to additional fixation means.
The duration of action of the fentanyl patch is 72 hours. Therefore, the drug should be worn continuously throughout the specified period, and then replace it with a new one. The second transdermal patch must be applied to another area without capturing the area of the previous application.
The drug based on fentanyl is not recommended to divide and cut.
Using a fentanyl patch for back pain and other parts of the body, you should be aware of possible side effects. The mentioned drug can cause such undesirable effects:
- respiratory depression, speech disorders, drowsiness, palpitations, hypersomnia, bradycardia, headache, arrhythmia, dizziness,
- confusion, tachycardia, depression, dyspnea, pharyngitis, anxiety, vomiting, nervousness, rhinitis,
- hallucinations, arterial hypotension, anorexia nervosa, delirium, vasodilation, involuntary muscle contractions, yawning, hypesthesia,
- euphoria, laryngospasm, amnesia, arterial hypertension, insomnia, abdominal pain, agitation, intestinal obstruction, tremor, constipation,
- paresthesia, nausea, amblyopia, xerostomia, asthenia, dyspepsia, sexual dysfunction, ataxia, hypoventilation, myoclonic convulsions, hiccups,
- hemoptysis, itching, obstructive pulmonary disease, diarrhea, exudation, painful flatulence, anaphylactic shock, rash, anaphylactic reactions, sweating, urinary retention, anaphylactoid reactions, ureteral spasm, rash,
- change in the appearance of the skin, microcracks, urinary tract infections, petechial erosion, peeling of the skin, scab, erythema, oliguria, bladder pain,
- conjunctivitis, malaise, fatigue, flu-like symptoms, swelling and a feeling of cold.
With prolonged use of fentanyl patch from pain in the back and other parts of the body, mental and physical dependence, tolerance, as well as short-term muscle stiffness can develop.
When using the agent in question, parallel intake of barbituric acid derivatives should be excluded, otherwise the latter can increase the likelihood of respiratory depression.
The simultaneous use of other drugs that suppress the central nervous system (opioids, tranquilizers, anxiolytics, general anesthetics, muscle relaxants, phenothiazine derivatives, etc.) can provoke the occurrence of hypoventilation, arterial hypotension, deep sedation or coma.
It is important to know!
Fentanyl-based drugs are prescribed as part of a comprehensive treatment of pain under the condition of an adequate social, medical and psychological assessment of the patient's condition.
With the development of severe side effects, the patient should be under the supervision of specialists for a day after removing the patch.
Unused and used transdermal preparations containing fentanyl must be stored out of the reach of small children.
People with elevated body temperature require careful observation by doctors (if necessary, adjust the dose of fentanyl).
Fentanyl patch analogs
The analogues of the drug under consideration (Fendivia) are such drugs as Fentanyl M Sandoz, Lunaldin, Fentadol Matrix, Durogezik Matrix, Fentadol Reservoir, Fentanyl, Dolforin. It should be remembered that replacing the main tool with similar ones is permissible only after consulting a doctor.
It should be remembered that with prolonged use of fentanyl can provoke the development of addiction. But the unique properties of the compound in question make the funds based on it very effective painkillers. In addition, transdermal therapeutic systems (TTS) with fentanyl slow down the rhythm of the heart and have a hypnotic effect.
Specialists especially note the effect of fentanyl drug, because its active ingredient is gradually and evenly absorbed in the skin tissues, which makes it possible to maintain a normal concentration of the substance. In the medical field, drugs with the addition of fentanyl are considered very effective and powerful painkillers, which are quite expensive.
Indications for use
Painful sensations are the most common condition in which the fentanyl patch is used. The instructions also indicate the following pathologies, in which it is permissible to use a fentanyl product:
In addition, fentanyl reduces the symptoms of oncology and is used as an effective short-term pain medication during recovery after surgical interventions. Fentanyl TTS itself can be used in situations where intravenous or oral administration of a substance is impossible for one reason or another.
Instructions for use
Any fentanyl products should only be prescribed by a medical professional. The unauthorized use of such drugs can lead to unpredictable consequences. It is also important to adhere to the rules of use, which are indicated in the instructions for use of the Fentanyl patch:
Before using the fentanyl patch, you must stop taking other anesthetics.
The very first use of fentanyl preparations should be under the supervision of a doctor so that she can identify how the patient's body reacts to the active substance. In the instructions for the patch there are additional instructions. So, the patch can be applied exclusively to an unirradiated and undamaged area of the skin. This is often the forearm, back, or chest area.
For persons with developmental delays and young children, a patch is applied only to the upper back, because it is from this place that the patient will not be able to remove it.
Vegetation is also removed from the skin in advance, after which the skin is washed with warm water.
For the patch Fentanyl, sterility and adequate sealing are important. If they are broken, the patch will not have any therapeutic effect. It is also important to stick the product on the skin immediately as it was removed from the pack.
It is forbidden to use heat activators like electric blankets or heating pads during the use of fentanyl TTS. It is also forbidden to direct heating devices and lamps to areas with a patch.
Use fentanyl agent locally. The first dose begins with a dose of 25 mg / h. Then the dosage will have to be reduced or increased. It is selected strictly individually.
To maintain the therapeutic effect, the patch must be changed every 3 days.
Contraindications and side effects
The main limitation is hypersensitivity to the components of the drug. In addition, patients are not allowed to use the patch:
- with hypotension
- with dyspepsia
- lactating and pregnant women
- with bradycardia
- patients with dermatological pathologies in the field of gluing a patch,
- in the presence of acute pain,
- under the age of 18.
It is contraindicated to use the patch Fentanyl and people with bronchial asthma and hypersensitivity to opioid substances.
Experts do not recommend using it after obstetric surgery.
Due to the fact that the active substance of the patch penetrates into the blood, the drug has an effect on almost all systems and organs of the human body. This sometimes leads to various side effects. Among the most common "side effects" stand out:
- insomnia or drowsiness,
- muscle spasms,
- nervousness and visual hallucinations,
- erythema or allergic form of dermatitis,
- impaired speech function,
- cardiac arrhythmia,
- increased sweating
- fatigue and weakness.
Consumers note that side effects are quite rare. Specialists, however, say that the patch does not have truly serious negative occurrences.
Cost and additional information
The drug can be stored for 24 months from the date of production. After this period it is undesirable to use it. It is necessary to store TTS in a dark and dry place where little children cannot reach. The optimum storage temperature is 24-26 degrees Celsius.
Fentanyl patches can now be bought at almost any Russian pharmacy. However, they are sold strictly by prescription.because they contain opioids. The price is directly dependent on the size of the plates and looks something like this:
- 100 g / h - 4900 rubles,
- 75 g / h - 3800 rubles
- 50 g / h - 3100 rubles,
- 25 g / h - 2200 rubles,
- 12.5 g / h - 1 800 rubles.
The high cost is explained by the effectiveness and quality of the product. As for manufacturers, the most reliable brands are Dolforin, Lunaldin, Fendivia, Durogezik Matrix, Fentadol.
Each patch has its own characteristics. Therefore, before using them, you need to carefully read the instructions for the patch with fentanyl.
My son somewhere picked up lichen. Some places on the skin were constantly dug up, and the child suffered from terrible pain. I tried many tools, including folk ones, but only fentanyl patch helped. His doctor prescribed us, determined the dosage and forbade it to be exceeded, since the composition of the solution has an opioid. Now the baby's condition has improved, but you have to regularly go to the hospital for procedures.
I play football for our area. 7 months ago a knee was severely injured. At first everything was fine, but then very unpleasant aching pains appeared. He went to the doctor, and he wrote me a prescription for the patch Fentanyl. The condition has improved markedly.
For a long time I have encountered the problem of hepatic colic. I tried a lot of everything, but only Fentanyl patch helped. However, it cannot be bought without a prescription. This is due to the fact that it includes hazardous substances, so you need to use the product under strict medical supervision.
Common fears and misconceptions
“What is the maximum dose of fentanyl?” Is a question often asked by both doctors and parents of children. Strong opioids do not have a maximum dose. The dose is increased until the patient achieves good analgesia. There is only the maximum starting (very first) dose - single and daily, with which the use of the drug is started and which is gradually brought to an effective pain reliever.
Very many health workers and parents are concerned about the question of whether the child will become an addict from their use. If the drug is prescribed according to indications - for the treatment of severe pain syndrome - mental dependence does not develop. Studies show that less than 1% of patients who correctly use strong opioid drugs for pain relief become mentally dependent on them, these patients, as a rule, had a history of addiction.
Physical dependence and tolerance begin to develop in all patients after 7-14 days from the start of taking narcotic analgesics. Therefore, if the doctor decides to stop taking the opiate, the withdrawal should occur according to a certain scheme, gradually.
The longer the drug was taken, the longer its withdrawal should go. You can find the drug withdrawal algorithm in the clinical guidelines.
Sometimes parents are very afraid to prescribe pain medications to their children. It is very sad when everyone is afraid, including a doctor, and there is no person who could intelligently explain why the use of an opioid drug is so necessary. If you feel that you are not competent to answer all questions, use the answers to frequently asked questions of parents, which are given in detail in the clinical recommendations. You can offer to get acquainted with them to parents who resist the prescription of the drug or want to cancel it.
In my practice, there were cases when my parents insisted on discontinuing the drug after achieving complete pain relief in the child - it seemed to them that everything was fine and the pain was gone forever. But, if the child has a pain syndrome, it is impossible to cancel the drug, since the pain will appear again. Of course, you need to be prepared for such situations, you must know how to competently and confidently explain, and dispel fears and doubts.
Clinical recommendations for the use of fentanyl
In 2012, the World Health Organization proposed a 2-step algorithm for pain relief in children. Non-narcotic analgesics are prescribed in the first step of the “ladder of pain relief” for mild pain (1-3 points out of 10 on the YOUR or FLACC scale). Strong narcotic analgesics, including morphine and fentanyl, are prescribed in the second stage with moderate (4-6 points out of 10) and severe pain (7 or more points out of 10).
Fentanyl is not a first line pain medication. The clinic should always have short-acting morphine, with which an analgesic dose is selected. No matter how the doctor wants to immediately appoint a fentanyl patch because of the convenience of its use, this should never be done.
Before prescribing a fentanyl patch, you need to select a dose using morphine, then calculate the required dosage of the patch with fentanyl, and also understand how it works - fentanyl enters the subcutaneous fat, and then it is absorbed into the blood. That is, it takes an average of 24 hours until an analgesic effect develops. This means that the first time you glue the patch, the child will not be anesthetized if you do not extend the drug he took earlier. The same principle should be considered when discontinuing the drug - for almost a day, fentanyl is contained in the subcutaneous tissue and absorbed into the blood.
In addition, if a child has breakthrough pain - it is unacceptable to stick an additional patch - you must give a quick-acting drug of short action: for mild pain (1-3 points out of 10 on the VAS or FLACC scale) - paracetamol, ibuprofen or ketorolac, with moderate pain ( 4-6 points out of 10) - tramadol or morphine, with severe pain (more than 7 points out of 10) - morphine.
When prescribing fentanyl, contraindications should be taken into account, such as hypersensitivity to opioid agonists or any component of the drug, acute respiratory depression, exacerbation of bronchial asthma, intestinal paresis, simultaneous administration or up to 14 days from the end of monoamine oxidase inhibitors, increased intracranial pressure and (or) cranial -brain injury without providing controlled ventilation of the lungs, coma, a day before and after surgery.
Fentanyl should also be used with caution in patients with bradycardia, bronchial asthma, hypotension, shock, obstructive or inflammatory bowel diseases, biliary tract diseases, convulsive disorders, hypothyroidism, adrenal insufficiency, diabetes mellitus, impaired consciousness, acute pancreatitis, myasthenia dysfunction, myasthenia gravis. , impaired renal function, intoxication psychosis, as well as at elevated body temperature.
It is necessary to enter drug by injection slowly, within 3-5 minutes, it is better - continuous infusion. Rapid administration may cause stiff chest muscles and difficulty breathing.
The appointment of fentanyl short (fast) action.
Starting single dose:
- transmucosally for the cheek or under the tongue for children aged 2-18 years and weighing more than 10 kg - 15 μg / kg (increase if necessary to a maximum dose of 400 μg),
- intranasally for children aged 2-18 years - 1-2 μg / kg (maximum starting single dose of 50 μg),
- intravenously (slowly over 3-5 minutes) for children under the age of 1 year - 1-2 mcg / kg every 2-4 hours, for children after 1 year - 1-2 mcg / kg every 30-60 minutes,
- continuous intravenous infusion for children under 1 year of age - start with a starting dose of 1-2 μg / kg (intravenously 3-5 minutes) intravenously, then titrate at a rate of 0.5-1 μg / kg per hour, children after 1 year - start with a starting dose of jet 1-2 μg / kg (in 3-5 minutes), then titrate at a rate of 1 μg / kg per hour.
Increase the dose of fentanyl until an analgesic effect is achieved.
Purpose of TTS with fentanyl
The dosage of the fentanyl patch is calculated on the basis of the equianalgetic daily dose of oral morphine. To calculate the dose of the patch, you need to divide the dose of morphine through the mouth by 3. There are also special transition tables from a specific dose of morphine to TTC with fentanyl. After gluing the patch, it takes about 18-24 hours to achieve pain relief.
After the patch is first glued, analgesics continue for 12-18 hours (for example, short-acting morphine every 4 hours or prolonged-action morphine every 12 hours). When re-sticking, this does not need to be done, since the depot of fentanyl in the subcutaneous fatty tissue works for 24 hours after peeling off the previous patch. The dosage of TTC with fentanyl increases gradually every 72 hours until an analgesic effect is achieved. With breakthrough pain, a short-acting drug is given.
When using fentanyl, parents of the child should be advised to keep a pain diary. From the diary, the medical worker will know the latest information about pain, which helps to quickly and efficiently select an analgesic regimen. For example, if TTC with fentanyl is used, in the pain diary it is necessary to note the date and time of gluing the patch, pain in points on a scale for assessing pain, side effects, the time of additional painkillers and their doses.
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- Fentanyl. State register of medicines date.
- A list of vital and essential medicines for medical use for 2018. Order of the Government of the Russian Federation of October 23, 2017 No. 2323-r.
- Savva N.N. Algorithms for assessing and treating pain in children. - M., 2015.
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