Butorphanol (Nasal Spray)
 BRAND NAMES
- International: Stadol
 MECHANISM OF ACTION
Butorphanol tartrate is a synthetically derived opioid agonist-antagonist analgesic of the phenanthrene series.
Butorphanol exhibits partial agonist and antagonist activity at the μ opioid receptor, as well as competitive antagonist activity and partial agonist activity at the κ opioid receptor
Its interactions with these receptors in the central nervous system apparently mediate most of its pharmacologic effects, including analgesia.
Onset of analgesia is within 15 minutes for the nasal spray doses.
Butorphanol nasal spray is indicated for the management of pain when the use of an opioid analgesic is appropriate.
Use for Pain
The usual recommended dose for initial nasal administration is 1 mg (1 spray in one nostril). Adherence to this dose reduces the incidence of drowsiness and dizziness. If adequate pain relief is not achieved within 60 to 90 minutes, an additional 1 mg dose may be given.
The initial dose sequence outlined above may be repeated in 3 to 4 hours as required after the second dose of the sequence.
Depending on the severity of the pain, an initial dose of 2 mg (1 spray in each nostril) may be used in patients who will be able to remain recumbent in the event drowsiness or dizziness occurs. In such patients single additional 2 mg doses should not be given for 3 to 4 hours.
- Patients hypersensitive to butorphanol
 WARNINGS AND PRECAUTIONS
Patients Dependent on Narcotics
Because of its opioid antagonist properties, butorphanol is not recommended for use in patients dependent on narcotics. Such patients should have an adequate period of withdrawal from opioid drugs prior to beginning butorphanol therapy. In patients taking opioid analgesics chronically, butorphanol has precipitated withdrawal symptoms such as anxiety, agitation, mood changes, hallucinations, dysphoria, weakness and diarrhea.
Because of the difficulty in assessing opioid tolerance in patients who have recently received repeated doses of narcotic analgesic medication, caution should be used in the administration of butorphanol to such patients.
Drug Abuse and Dependence
Drug Abuse: Butorphanol tartrate, by all routes of administration, has been associated with episodes of abuse. Of the cases received, there were more reports of abuse with the nasal spray formulation than with the injectable formulation.
Physical Dependence, Tolerance and Withdrawal: Prolonged, continuous use of butorphanol tartrate may result in physical dependence or tolerance (a decrease in response to a given dose). Abrupt cessation of use by patients with physical dependence may result in symptoms of withdrawal.
Note - Proper patient selection, dose and prescribing limitations, appropriate directions for use, and frequent monitoring are important to minimize the risk of abuse and physical dependence
Hypotension associated with syncope during the first hour of dosing with butorphanol tartrate nasal spray has been reported rarely, particularly in patients with past history of similar reactions to opioid analgesics. Therefore, patients should be advised to avoid activities with potential risks.
Head Injury and Increased Intracranial Pressure
As with other opioids, the use of butorphanol in patients with head injury may be associated with carbon dioxide retention and secondary elevation of cerebrospinal fluid pressure, drug-induced miosis, and alterations in mental state that would obscure the interpretation of the clinical course of patients with head injuries. In such patients, butorphanol should be used only if the benefits of use outweigh the potential risks.
Disorders of Respiratory Function or Control
Butorphanol may produce respiratory depression, especially in patients receiving other CNS active agents, or patients suffering from CNS diseases or respiratory impairment.
Hepatic and Renal Disease
The initial dose sequence of butorphanol tartrate nasal spray should be limited to 1 mg followed, if needed, by 1 mg in 90 to 120 minutes. The repeat dose sequence in these patients should be determined by the patient’s response rather than at fixed times but will generally be at intervals of no less than 6 hours.
Because butorphanol may increase the work of the heart, especially the pulmonary circuit, the use of butorphanol in patients with acute myocardial infarction, ventricular dysfunction, or coronary insufficiency should be limited to those situations where the benefits clearly outweigh the risk.
Severe hypertension has been reported rarely during butorphanol therapy. In such cases, butorphanol should be discontinued and the hypertension treated with antihypertensive drugs. In patients who are not opioid dependent, naloxone has also been reported to be effective.
Use in Ambulatory Patients
1) Opioid analgesics, including butorphanol, impair the mental and physical abilities required for the performance of potentially dangerous tasks such as driving a car or operating machinery. Effects such as drowsiness or dizziness can appear, usually within the first hour after dosing. These effects may persist for varying periods of time after dosing. Patients who have taken butorphanol should not drive or operate dangerous machinery for at least 1 hour and until the effects of the drug are no longer present.
2) Alcohol should not be consumed while using butorphanol. Concurrent use of butorphanol with drugs that affect the central nervous system (e.g., alcohol, barbiturates, tranquilizers, and antihistamines) may result in increased central nervous system depressant effects such as drowsiness, dizziness, and impaired mental function.
3) Butorphanol is one of a class of drugs known to be abused and thus should be handled accordingly.
4) Patients should be instructed on the proper use of butorphanol nasal spray.
Concurrent use of butorphanol with central nervous system depressants (e.g., alcohol, barbiturates, tranquilizers, and antihistamines) may result in increased central nervous system depressant effects. When used concurrently with such drugs, the dose of butorphanol should be the smallest effective dose and the frequency of dosing reduced as much as possible when administered concomitantly with drugs that potentiate the action of opioids.
The analgesic effect of butorphanol tartrate nasal spray may be diminished when it is administered shortly after sumatriptan nasal spray, but by 30 minutes any such reduction in effect should be minimal.
The safety of using butorphanol tartrate nasal spray and Isumatriptan nasal spray during the same episode of migraine has not been established. However, it should be noted that both products are capable of producing transient increases in blood pressure.
The fraction of butorphanol tartrate nasal spray absorbed is unaffected by the concomitant administration of a nasal vasoconstrictor (oxymetazoline), but the rate of absorption is decreased. Therefore, a slower onset can be anticipated if butorphanol tartrate nasal spray is administered concomitantly with, or immediately following, a nasal vasoconstrictor.
 PREGNANCY AND LACTATION
- Pregnancy Category C (US). Butorphanol tartrate should be used during pregnancy only if the potential benefit justifies the potential risk to the infant.
 SIDE EFFECTS
The most frequently reported adverse experiences across all clinical trials with butorphanol tartrate injection and butorphanol tartrate nasal spray were somnolence (43%), dizziness (19%), nausea and/or vomiting (13%). In long-term trials with butorphanol tartrate nasal spray only, nasal congestion (13%) and insomnia (11%) were frequently reported.
The following adverse experiences were reported at a frequency of 1% or greater in clinical trials, and were considered to be probably related to the use of butorphanol:
- Body as a Whole: asthenia/lethargy, headache, sensation of heat
- Cardiovascular: vasodilation, palpitations
- Digestive: anorexia, constipation, dry mouth, nausea and/or vomiting, stomach pain
- Nervous: anxiety, confusion, dizziness, euphoria, floating feeling, insomnia, nervousness, paresthesia, somnolence, tremor
- Respiratory: bronchitis, cough, dyspnea, epistaxis, nasal congestion, nasal irritation, pharyngitis, rhinitis, sinus congestion, sinusitis, upper respiratory infection
- Skin and Appendages: sweating/clammy, pruritus
- Special Senses: blurred vision, ear pain, tinnitus, unpleasant taste
The following adverse experiences were reported with a frequency of less than 1% in clinical trials, and were considered to be probably related to the use of butorphanol:
- Cardiovascular: hypotension, syncope
- Nervous: abnormal dreams, agitation, dysphoria, hallucinations, hostility, withdrawal symptoms
- Skin and Appendages: rash/hives
- Urogenital: impaired urination
The following infrequent additional adverse experiences were reported in a frequency of less than 1% of the patients studied in short-term butorphanol tartrate nasal spray trials and under circumstances where the association between these events and butorphanol administration is unknown. They are being listed as alerting information for the physician.
- Body as a Whole: edema
- Cardiovascular: chest pain, hypertension, tachycardia
- Nervous: depression
- Respiratory: shallow breathing