Fentanyl

Fentanyl is an analgetic narcotic type.

[1], [2],

Indications Fentanyl

It is used in such situations:

• anesthesia for a short period of time - as an anesthetic during induction or premedication, and also as a supporting agent in the post-surgical period;
• to provide a strong analgesic effect, in addition to local or general anesthesia;
• in combination with neuroleptics (for example, with droperidol) during premedication, and in addition as an auxiliary medicine for local or general anesthesia;
• as an anesthetic in people with an increased likelihood of complications, during the execution of heavy operations (for example, in the heart).

In addition, Fentanyl can be used in orthopedic or neurological procedures - it is prescribed as an auxiliary analgesic.

[3], [4], [5], [6]

Release form

The release takes place in the form of an injection liquid (in a 50 ml bottle), and also in the form of a transdermal therapeutic system - 5 special packets inside the box.

[7], [8], [9]

Pharmacodynamics

Medication has a sedative and analgesic effect. During application, it should be remembered that changes in ventilation of pulmonary alveoli and respiratory frequency may be more prolonged than analgesic effects.

As the portion increases, the pulmonary metabolism is weakened. If too large portions are used, apnea may develop.

Fentanyl has a less pronounced emetic effect than substances such as meperidine or morphine.

[10], [11], [12], [13], [14]

Pharmacokinetics

The distribution of the substance is 1.7 minutes, and the redistribution period is 13 minutes. The half-life of drugs is 219 minutes.

The indicator of the distribution volume of the drug is 4 l / kg. The ability of the plasma protein to synthesize is weakened as the ionization of the drug increases. Changes in pH can affect the distribution of medication between the CNS and plasma.

The active ingredient cumulates inside the muscles of the skeleton, as well as fatty tissues, and then is released at low speed, penetrating into the blood. Conversion of the drug occurs inside the liver with a high frequency.

Approximately 75% of the intravenously administered dosing method is excreted together with urine (most are decay products). With urine, less than 10% of the unchanged element is excreted. Approximately 9% of the portion of the drug is excreted (as decay products) with feces.

The active action of Fentanyl begins to manifest almost immediately after intravenous injection. However, the maximum intensity of anesthesia lasts no more than a few minutes. On average, the analgesic effect lasts approximately 0.5-1 hour (with IV injection doses up to 2 ml of the solution (100 μg)). With the / m injections the drug starts to act 7-8 minutes after the procedure, and the total duration of the drug effect is approximately 2 hours.

[15], [16], [17], [18], [19], [20],

Dosing and administration

Prescribers can be prescribed only by doctors with the knowledge and experience of handling opioid drugs of powerful effect, when used to treat chronic pain.

Since there is a probability of suppression of respiratory activity, the drug is prescribed only to those persons who have a good tolerability of such remedies. At the time of using Fentanyl, it is necessary to minimize the use of other anesthetics.

Resistant to the effects of opioids are people who were injected daily with at least 60 mg of morphine, 30 mg of oxycodone, 8 mg of hydromorphone, or other opioid medicines for 7 days or longer.

Selection of portions for each patient is carried out individually, taking into account the history of the use of analgesics during therapy, as well as the risk factors for the appearance of drug dependence in a person.

After the appointment of any portion of the drug, the doctor should closely monitor the patient's reaction, for example, suppression of respiratory activity, especially during the first 24-72 hours from the start of the course, when the drug reaches its maximum inside the serum.

Dimensions of dosage portions.

During the preparation of an adult, 0.05-0.1 mg of the drug is administered intravenously to the surgical procedure (in combination with droperidol (2.5-5 mg)). This should be done approximately 15 minutes before the introduction of anesthesia. As surgical anesthesia: intravenously, 0.05-0.2 mg of the substance is administered every 30 minutes.

In the case of preparation of the child for the surgical procedure, 0.002 mg / kg of the drug should be administered. Surgical anesthesia requires an IV dose of 0.01-0.15 mg / kg or an IM injection of 0.15-0.25 mg / kg. To maintain surgical anesthesia, you need an intramuscular injection of 0.001-0.002 mg / kg of the drug.

The plaster is required to be applied to the epidermis (flat area) for 72 hours. An important condition for the procedure is the minimum amount of hair on the treatment site, as well as the absence of noticeable signs of irritation of the allergic nature.

[26], [27], [28], [29], [30]

Use Fentanyl during pregnancy

Do not use Fentanyl for lactation or pregnancy.

Contraindications

The main contraindications:

• the presence of intolerance against opioid medicines;
• bronchial asthma;
• dependence on narcotic substances;
• Conditions in which suppression of the respiratory center function is noted;
• performance of obstetrical procedures;
• insufficiency of respiratory function;
• presence of suspicion of intestinal obstruction.

[21], [22], [23], [24]

Side effects Fentanyl

Medication can cause a variety of negative effects:

• in the case of excessive or prolonged use of drugs can develop drug dependence;
• severe forms of respiratory function disorders;
• decrease in blood pressure;
• bradycardia;
• short muscular rigidity;
• moderate bronchoconstriction.

[25]

Overdose

When acute poisoning, a feeling of drowsiness, suppression of respiratory activity, muscle spasm, coma or stupor, a decrease in the level of pressure and bradycardia is noted.

Occasionally, an overdose of the medicine may cause the death of the patient.

[31], [32]

Interactions with other drugs

Combination with antidepressants.

The combination with other drugs that affect the function of the central nervous system (including tranquilizers, hypnotics or sedatives, opioids and general anesthetic agents) can lead to an increased likelihood of disrupting the respiratory system, deep sedation and coma, and also to death. When used simultaneously with any of the above-described agents, the dosage of one of them should be reduced.

Medications that slow down the activity of CYP3A4.

Due to the fact that isoenzyme CYP3A4 is an important element in the metabolism of the drug, drugs that slow its activity can reduce the values of clearance of Fentanyl, which increases its values inside the plasma and prolongs the duration of opioid exposure. Similar effects may be more intense when combined with 3A4 inhibitors.

Substances inducing the function of CYP3A4.

Elements that induce CYP450 3A4 are able to induce the metabolism of the drug, which causes its clearance to increase, and the level inside the plasma, on the contrary, decreases. As a result, there is a lack of drug effectiveness or the possible emergence of withdrawal syndrome in people who subsequently acquire drug dependence.

Combination with MAOI.

The combination of the drug with MAOI has not yet been studied sufficiently, which is why the simultaneous use of this substance is completely prohibited.

[33], [34], [35], [36],

Storage conditions

Fentanyl is required to be kept in a dry and dark place, closed from penetration of young children. The temperature level should not exceed 25 ° C.

[37]

Shelf life

Fentanyl can be used within 24 months from the date of release of the drug.

[38], [39], [40]

[41], [42], [43]

Application for children

It is forbidden to prescribe drugs for children under 2 years of age.

Analogues

Analogues of the drug are the drugs Lunaldin with Dolforin, Fentadol with Durogesic Matrix, and also Fendivia.

[44], [45], [46], [47]

Reviews

Fentanyl receives quite different reviews regarding the nature of the drug exposure. Often, patients who have used it, are not able to adequately assess its effectiveness, which is due to the severity of the pathologies in which the drug is prescribed.

But most experts consider the drug to be quite effective, because it very qualitatively eliminates strong pain during treatment, and also after surgical procedures.