Butorphanol - instructions for use, dose, side effects, contraindications

Pharmacodynamics:Opioid analgesic, opioid receptor antagonist agonist. A potent agonist of opioid κ-receptors and an antagonist of opioid μ receptors. The effect on sigma-receptors is due to some psychotomimetic action and the ability to sometimes cause dysphoria.

Butorphanol violates pain impulses in the afferent pathways of the central nervous system (impaired transmission of impulses from the end of the primary afferents to intercalary neurons of the spinal cord). By stimulating opioid receptors in the presynaptic endings of the axons of the primary afferents, it reduces the release of substance P and glutamate, thus impairing the transmission of pain impulses to the intercalary neurons of the posterior horns of the spinal cord.Due to the stimulation of postsynaptic opioid receptors, the process of depolarization of the postsynaptic membrane is disrupted and the activation of the inserted neurons is inhibited by the mediator. Strengthens the inhibitory effects of the descending antinociceptive system on pain impulses in the afferent pathways of the central nervous system.

Butorphanol changes the emotional color of pain and reaction to it.

Pharmacokinetics:

Absorbed into the systemic blood stream with intramuscular injection 10-15 minutes later, with the nasal mucosa after 15 minutes. Binding to plasma proteins - 80%. Passes histohematological barriers, including blood-brain barrier and placental barrier. Metabolised in the liver. It is excreted (mainly in the form of metabolites) with urine (70-80%) and with feces (15%); Unchanged in the urine is only 5%. It is secreted by the lactating mammary gland, the concentration in the breast milk of the mother receiving the drug intramuscularly at a dose of 2 mg 4 times a day is 4 μg / l. Half-life in young patients is 4.7 hours, in the elderly - 6.6 hours, in patients with severe renal dysfunction - 10.5 hours.

After intravenous administration, the effect occurs immediately, with intramuscular injection, within 10 minutes. The maximum analgesic effect develops a few minutes after intravenous and 30-60 minutes after intramuscular administration, is maintained for 3-4 hours.

Indications:Pain syndrome of moderate to severe severity of different etiology, incl. postoperative, during childbirth; Premedication and balanced anesthesia.

ICD-10

XVIII.R50-R69.R52.0 Acute pain

XVIII.R50-R69.R52.1 Constant unrestrained pain

XVIII.R50-R69.R52.2 Another constant pain

Contraindications:Hypersensitivity, pregnancy (except anesthesia of childbirth), breast-feeding.

Carefully:

Drug addiction, head trauma, intracranial hypertension, respiratory failure, chronic heart failure, extensive myocardial infarction, coronary insufficiency, arterial hypertension, age under 18 years (efficacy and safety not established), elderly (over 65 years).

Contraindicated in severe violations of liver function.

In case of violations of the liver function, correction of the dosing regimen is required.

Contraindicated in severe renal dysfunction.

In case of violations of the kidneys, correction of the dosing regimen is required.

Pregnancy and lactation:

Recommendations Food and Drug Administration (US Food and Drug Administration) category C. The risk of dependence in the fetus and the development of the phenomenon of withdrawal in a newborn (irritability, convulsions, excessive tearfulness, tremor, lively reflexes, fever, nausea, diarrhea, sneezing and yawning). Adequate and well-controlled studies on humans have not been conducted.

Penetrates into breast milk in low doses. Do not apply!

Dosing and Administration:

Intravenously, intramuscularly. Doses are set individually. For relief of pain syndrome - intravenously or intramuscularly in medium doses - 1 and 2 mg (respectively) once, if necessary (depending on the intensity of pain) - 0.5-2 mg intravenously or 1-4 mg intramuscularly every 3-4 hours. In elderly patients and in violation of the liver and / or kidney function, the dose is reduced by a factor of 2.

Before surgery - 2 mg intravenously, for 60-90 minutes, during the operation - 0.5-1 mg intravenously in several introductions.

In parturient women - 1-2 mg intravenously or intramuscularly, if necessary - 1 time, again after 4 hours.

Side effects:

Drowsiness, dizziness, nausea and vomiting.

From the nervous system and sensory organs: anxiety, confusion, euphoria, insomnia, nervousness, paresthesia, drowsiness, fatigue, lethargy, headache, tremor, blurred vision, eye pain, ringing in the ears; unusual dreams, agitation, dysphoria, hallucinations, hostility, vertigo, withdrawal syndrome, depression.

From the cardiovascular system: vasodilation, palpitations; lowering blood pressure or increasing blood pressure, fainting, tachycardia, chest pain.

On the part of the organs of the gastrointestinal tract: anorexia, constipation, dryness of the oral mucosa, epigastric pain.

Allergic reactions: rash, hives.

Other: fever, sweating, itching; decrease in urination, shallow breathing.

In postmarketing observations were noted: apnea, seizures, delirium, drug dependency, transient difficulty of speech and movement (associated with the excessive influence of the drug).

Overdose:

Symptoms of acute and chronic overdose: cold sticky sweat, confusion, dizziness, drowsiness, lowering of blood pressure, nervousness, fatigue, miosis, bradycardia, severe weakness, slow labored breathing, hypothermia, anxiety, dry mouth, delirious psychosis, intracranial hypertension up to the violation of cerebral circulation), hallucinations, muscle rigidity, convulsions, in severe cases - loss of consciousness, respiratory arrest, coma.

Treatment: gastric lavage, restoring breathing and maintaining cardiac activity and blood pressure; intravenous the introduction of a specific antagonist opioid analgesics - naloxone in a single dose of 0.2-0.4 mg with repeated administration in 2-3 minutes to achieve a total dose of 10 mg; the initial dose for children is 0.01 mg / kg.

Interaction:

Alcohol, drugs that depress the central nervous system (barbiturates, benzodiazepines, antipsychotics) - potentiating oppressive effects on the central nervous system, including the respiratory center.

Anticholinergic, antidiarrheal agents - risk of severe constipation and acute delayurine.

Antihypertensive drugs, especially ganglion blockers and diuretics, - potentiation of the hypotensive effect.

Local vasoconstrictors decrease the efficacy of butorphanol with intranasal application.

Buprenorphine - a decrease in the therapeutic effect of butorphanol.

Other drugs that cause drug dependence - increased risk of drug dependence.

Metoclopramide - decreased prokinetic activity of metoclopramide.

Miorelaxants - potentiation of respiratory depression.

Naltrexone, naloxone, nalorfin - antidotes of narcotic analgesics, eliminate all their pharmacological effects, including cause withdrawal syndrome in patients with drug dependence to them.

Narcotic analgesics are antagonism, the phenomenon of cancellation is possible.

Pharmaceutically incompatible with barbiturates, diazepam.

With caution should be used simultaneously with monoamine oxidase inhibitors because of possible overexcitation or inhibition with the emergence of hyper- or hypotensive crises.

Special instructions:

The risk of psychotomimetic effect is lower than that of pentazocine. According to the degree of anesthesia, respiratory depression and duration of action corresponds to morphine.The drug is best used in acute, than with chronic pain. With myocardial infarction and heart failure, it is better to use morphine.

It is not indicated for short-term operations due to the possibility of prolonged post-acute respiratory depression.

Do not use with abdominal pain of unclear etiology.

Avoid simultaneous use of alcohol.

Impact on the ability to drive vehicles and manage mechanisms

During the treatment period, you should not engage in potentially hazardous activities requiring increased attention, speed of psychomotor reactions.

Instructions

Butorphanol (Butorphanolum)