Buprenorphine, Buprenorphine Hydrochloride and Levodopa/Carbidopa

• Generic Name: buprenorphine
• Dosage Forms: n.a.
• Other Brand Names: Belbuca, Buprenex, Butrans, Probuphine, Sublocade, Subutex

Used parenterally for relief of pain that is severe enough to require opiate analgesia and for which alternative treatment options (e.g., nonopiate analgesics, opiate-containing fixed combinations) have not been, or are not expected to be, adequate or tolerated.

Has been used parenterally for management of pain such as that associated with acute and chronic medical disorders including cancer, trigeminal neuralgia, accidental trauma, ureteral calculi, and MI.

Used parenterally for management of postoperative pain in patients who have undergone various types of surgery, including neurologic, cardiovascular (e.g., CABG, valve replacement), cesarean section, gynecologic, abdominal (e.g., cholecystectomy, bowel resection), urologic, general (e.g., head and neck, breast), and orthopedic (e.g., total hip replacement, spinal fusion).

Used transdermally or buccally for management of pain that is severe enough to require daily, around-the-clock, long-term opiate analgesia and for which alternative treatment options (e.g., nonopiate analgesics, immediate-release opiates) are inadequate. Do not use on an as-needed (“prn”) basis.

Has been used parenterally for preoperative sedation and analgesia and as an adjunct to surgical anesthesia.

Do not use oral transmucosal formulations that are intended for use in the treatment of opiate dependence for analgesia. Fatal overdosage reported with such use in opiate-naive individuals.

In symptomatic treatment of acute pain, reserve opiate analgesics for pain resulting from severe injuries, severe medical conditions, or surgical procedures, or when nonopiate alternatives for relieving pain and restoring function are expected to be ineffective or are contraindicated. Use smallest effective dosage for shortest possible duration since long-term opiate use often begins with treatment of acute pain. Optimize concomitant use of other appropriate therapies. (See Managing Opiate Therapy for Acute Pain under Dosage and Administration.)

Generally use opiates for management of chronic pain (i.e., pain lasting >3 months or past the time of normal tissue healing ) that is not associated with active cancer treatment, palliative care, or end-of-life care only if other appropriate nonpharmacologic and nonopiate pharmacologic strategies have been ineffective and expected benefits for both pain relief and functional improvement are anticipated to outweigh risks.

If used for chronic pain, opiate analgesics should be part of an integrated approach that also includes appropriate nonpharmacologic modalities (e.g., cognitive-behavioral therapy, relaxation techniques, biofeedback, functional restoration, exercise therapy, certain interventional procedures) and other appropriate pharmacologic therapies (e.g., nonopiate analgesics, analgesic adjuncts such as selected anticonvulsants and antidepressants for certain neuropathic pain conditions).

Available evidence insufficient to determine whether long-term opiate therapy for chronic pain results in sustained pain relief or improvements in function and quality of life or is superior to other pharmacologic or nonpharmacologic treatments. Use is associated with serious risks (e.g., opiate use disorder, overdose). (See Managing Opiate Therapy for Chronic Noncancer Pain under Dosage and Administration.)

Used sublingually or buccally for treatment of opiate dependence (opiate use disorder) in an office-based outpatient setting (designated an orphan drug by FDA for this use); used alone and in fixed combination with naloxone (buprenorphine/naloxone).

Although buprenorphine traditionally has been preferred for the initial (i.e., induction) phase of treatment, additional experience indicates that either buprenorphine or buprenorphine/naloxone may be used for induction therapy in patients dependent on heroin or other short-acting opiates. The manufacturers and some experts recommend use of buprenorphine alone for induction in patients dependent on long-acting opiates; adequate and well-controlled studies of buprenorphine/naloxone are lacking in this population.

Generic buprenorphine/naloxone sublingual tablets (i.e., generic equivalents of Suboxone sublingual tablets; branded formulation no longer commercially available in US) are labeled in US only for maintenance treatment, but have been used (similarly to other oral transmucosal buprenorphine/naloxone preparations) for induction.

Following induction, buprenorphine/naloxone is preferred for maintenance treatment when use includes unsupervised administration since the presence of naloxone (an opiate antagonist) in the formulation should discourage parenteral misuse. Limit use of buprenorphine alone in an unsupervised setting to pregnant women and patients who cannot tolerate naloxone. (See Hepatic Impairment and also Pregnancy under Cautions.)

Buprenorphine extended-release sub-Q injection used for the treatment of moderate to severe opiate dependence in patients who have initiated treatment with an oral transmucosal buprenorphine-containing preparation followed by dosage adjustment for ≥7 days. (See Dosage: Opiate Dependence, under Dosage and Administration.)

Buprenorphine subdermal implants used for maintenance treatment of opiate dependence in patients who have achieved and maintained prolonged clinical stability on a low to moderate dosage of an oral transmucosal buprenorphine-containing preparation (i.e., a transmucosal dosage that provides blood buprenorphine concentrations comparable to or lower than those provided by the subdermal implants). (See Dosage: Opiate Dependence, under Dosage and Administration.)

Safety and efficacy of transdermal buprenorphine for treatment of opiate dependence not established.

• Generic Name: carbidopa / levodopa
• Dosage Forms: n.a.
• Other Brand Names: Parcopa, Rytary, Sinemet, Sinemet CR, Duopa

Levodopa is used for symptomatic treatment of parkinsonian syndrome (e.g., parkinsonism, idiopathic Parkinson disease [paralysis agitans]); also used for postencephalitic parkinsonism and symptomatic parkinsonian syndrome resulting from carbon monoxide intoxication or manganese intoxication.

Carbidopa is used in conjunction with levodopa to inhibit decarboxylation of peripheral levodopa and increase the amount of levodopa available for transport to the brain.

Levodopa (in combination with carbidopa) is the most effective drug for relieving motor symptoms of parkinsonian syndrome and is considered the drug of choice for this use.

Levodopa provides symptomatic relief (e.g., akinesia, rigidity, tremor) and improves functional ability; however, effectiveness decreases over time and most patients develop motor fluctuations and dyskinesias (drug-induced involuntary movements) with long-term use.

Strategies for reducing the risk of motor complications associated with long-term levodopa therapy include adjusting dosage of levodopa, adding adjunctive antiparkinsonian agents (e.g., dopamine agonist [e.g., pramipexole, ropinirole, rotigotine], selective monoamine oxidase [MAO]-B inhibitor [e.g., rasagiline, safinamide, selegiline], catechol-O-methyltransferase [COMT] inhibitor [entacapone, tolcapone], amantadine), or initiating therapy with other antiparkinsonian agents first to delay use of levodopa. Delayed approach is often used in younger patients who have a higher risk of developing motor complications. Levodopa generally is used for initial therapy in patients >70 years of age, those with cognitive impairment, and those with severe disease.

Not effective in the management of extrapyramidal effects induced by antipsychotic agents (e.g., phenothiazines).