Addiction Aids

Acamprosate (campral ® )

Buprenorphine (buprenex®, subutex ®)

Disulfiram (antabuse ® )

Naltrexone (revia®, vivitrol™)

Suboxone ®(buprenorphine and naloxone)

Varenicline (chantix ® )

Acamprosate (campral ® )

CLINICAL PHARMACOLOGY
Pharmacodynamics
The mechanism of action of acamprosate in maintenance of alcohol abstinence is not completely understood. Chronic alcohol exposure is hypothesized to alter the normal balance between neuronal excitation and inhibition. In vitro and in vivo studies in animals have provided evidence to suggest acamprosate may interact with glutamate and GABA neurotransmitter systems centrally, and has led to the hypothesis that acamprosate restores this balance.

Pharmacodynamic studies have shown that acamprosate calcium reduces alcohol intake in alcohol-dependent animals in a dose-dependent manner and that this effect appears to be specific to alcohol and the mechanisms of alcohol dependence.

Acamprosate calcium has negligible observable central nervous system (CNS) activity in animals outside of its effects on alcohol dependence, exhibiting no anticonvulsant, antidepressant, or anxiolytic activity.

The administration of acamprosate calcium is not associated with the development of tolerance or dependence in animal studies.

CAMPRAL® is not known to cause alcohol aversion and does not cause a disulfiram-like reaction as a result of ethanol ingestion.

INDICATIONS AND USAGE
CAMPRAL® is indicated for the maintenance of abstinence from alcohol in patients with alcohol dependence who are abstinent at treatment initiation. Treatment with CAMPRAL® should be part of a comprehensive management program that includes psychosocial support.

The efficacy of CAMPRAL® in promoting abstinence has not been demonstrated in subjects who have not undergone detoxification and not achieved alcohol abstinence prior to beginning CAMPRAL® treatment. The efficacy of CAMPRAL® in promoting abstinence from alcohol in polysubstance abusers has not been adequately assessed.

Dosage: two 333 mg tablets (each dose should total 666 mg) taken three times daily. A lower dose may be effective in some patients.

Treatment with CAMPRAL should be initiated as soon as possible after the period of alcohol withdrawal, when the patient has achieved abstinence, and should be maintained if the patient relapses.

Dosage in Renal Impairment
[30-50 mL/min]: starting dose: 333 mg tid.
[<30 ml/min]: AVOID USE.

Supplied: 333mg tablet

Buprenorphine (buprenex®, subutex ®)

Dosing (Adults):
Acute pain (moderate to severe): I.M.: Initial: Opiate-naive: 0.3 mg every 6-8 hours as needed; initial dose (up to 0.3 mg) may be repeated once in 30-60 minutes after the initial dose if needed; usual dosage range: 0.15-0.6 mg every 4-8 hours as needed. Slow I.V.: Initial: Opiate-naive: 0.3 mg every 6-8 hours as needed; initial dose (up to 0.3 mg) may be repeated once in 30-60 minutes after the initial dose if needed.

Opioid dependence: Sublingual: Induction: Range: 12-16 mg/day (doses during an induction study used 8 mg on day 1, followed by 16 mg on day 2; induction continued over 3-4 days). Treatment should begin at least 4 hours after last use of heroin or short-acting opioid, preferably when first signs of withdrawal appear. Titrating dose to clinical effectiveness should be done as rapidly as possible to prevent undue withdrawal symptoms and patient drop-out during the induction period. Maintenance: Target dose: 16 mg/day; range: 4-24 mg/day; patients should be switched to the buprenorphine/naloxone combination product for maintenance and unsupervised therapy.

Supplied:
Injection, solution:
Buprenex®: 0.3 mg/mL (1 mL)

Tablet, sublingual:
Subutex®: 2 mg, 8 mg
Oval white tablets containing 2mg or 8 mg buprenorphine.

Buprenorphine is a partial opiate agonist (agonist and antagonist properties.). Like most partial agonists, it has a safer profile than that of a full agonist. It exhibits a ceiling effect, which means that once a certain receptor occupancy desired dosage level has been achieved, additional dosing does not produce additional effects, including eliminating the typical possible opiate overdose effects of respiratory depression and/or death. By combining it with Naloxone, in a 4:1 ratio, it is hoped that it will prevent both diversion of the drug and intravenous injection. The withdrawal syndrome seen with buprenorphine is much milder than that of other full agonist opiates.

Buprenorphine has been approved by the FDA for use in the United States as an opiate detoxification and opiate maintenance agent. There will be two forms of the medication (available in 2 mg and 8 mg sublingual tablets: Subutex - buprenorphine alone and Suboxone, which is Buprenorphine combined with Naloxone. This combination form prevents intravenous use of the tablet after crushing; in which the user would get an antagonist effect of the naloxone, or at the least, a diminished opiate effect. Doses for opioid dependence will range from 2 mg to 32 mg, with the average being approximately 16 mg. and the medication can be used for detoxification or maintenance treatment.

Disulfiram (antabuse ® )

INDICATIONS AND USAGE
Disulfiram is an aid in the management of selected chronic alcohol patients who want to remain in a state of enforced sobriety so that supportive and psychotherapeutic treatment may be applied to best advantage.

Disulfiram is not a cure for alcoholism. When used alone, without proper motivation and supportive therapy, it is unlikely that it will have any substantive effect on the drinking pattern of the chronic alcoholic.

CONTRAINDICATIONS
Patients who are receiving or have recently received metronidazole, paraldehyde, alcohol, or alcohol-containing preparations, e.g., cough syrups, tonics and the like, should not be given disulfiram.

Disulfiram is contraindicated in the presence of severe myocardial disease or coronary occlusion, psychoses, and hypersensitivity to disulfiram or to other thiuram derivatives used in pesticides and rubber vulcanization.

WARNINGS

Disulfiram should never be administered to a patient when he is in a state of alcohol intoxication, or without his full knowledge.

The physician should instruct relatives accordingly.

The patient must be fully informed of the disulfiram-alcohol reaction. He must be strongly cautioned against surreptitious drinking while taking the drug, and he must be fully aware of the possible consequences. He should be warned to avoid alcohol in disguised forms, i.e., in sauces, vinegars, cough mixtures, and even in aftershave lotions and back rubs. He should also be warned that reactions may occur with alcohol up to 14 days after ingesting disulfiram.

The Disulfiram-Alcohol Reaction:
Disulfiram plus alcohol, even small amounts, produce flushing, throbbing in head and neck, throbbing headache, respiratory difficulty, nausea, copious vomiting, sweating, thirst, chest pain, palpitation, dyspnea, hyperventilation, tachycardia, hypotension, syncope, marked uneasiness, weakness, vertigo, blurred vision, and confusion. In severe reactions there may be respiratory depression, cardiovascular collapse, arrhythmias, myocardial infarction, acute congestive heart failure, unconsciousness, convulsions, and death.

The intensity of the reaction varies with each individual, but is generally proportional to the amounts of disulfiram and alcohol ingested. Mild reactions may occur in the sensitive individual when the blood alcohol concentration is increased to as little as 5 to 10 mg per 100 mL. Symptoms are fully developed at 50 mg per 100 mL, and unconsciousness usually results when the blood alcohol level reaches 125 to 150 mg.

The duration of the reaction varies from 30 to 60 minutes, to several hours in the more severe cases, or as long as there is alcohol in the blood.

Concomitant Conditions:
Because of the possibility of an accidental disulfiram-alcohol reaction, disulfiram should be used with extreme caution in patients with any of the following conditions: diabetes mellitus, hypothyroidism, epilepsy, cerebral damage, chronic and acute nephritis, hepatic cirrhosis or insufficiency.

Initial Dosage Schedule: In the first phase of treatment. a maximum of 500 mg daily is given in a single dose for one to two weeks. Although usually taken in the morning, Disulfiram may be taken on retiring by patients who experience a sedative effect. Alternatively, to minimize, or eliminate, the sedative effect, dosage may be adjusted downward.
Maintenance Regimen: The average maintenance dose is 250 mg daily (range, 125 to 500 mg). Maximum daily dose is 500 mg. Duration of therapy is to continue until the patient is fully recovered socially and a basis for permanent self control has been established. Maintenance therapy may be required for months or even years.
Supplied: 250 mg, 500mg tablet.

Antabuse is an older medication that is worth considering in some patients to help them remain in recovery. Antabuse produces a sensitivity to alcohol which results in a highly unpleasant reaction when the individual under treatment ingests alcohol. MOA: Antabuse blocks the oxidation of alcohol. A product of this oxidation is acetaldehyde. If antabuse is taken, the metabolism stops at the point of acetaldehyde production and there will be an increase in the concentration of acetaldehyde 5 - 10 times higher than in normal alcohol metabolism. The accumulation of acetaldehyde produces the " ANTABUSE - ALCOHOL REACTION". This reaction can range from a flush and throbbing in the head and neck to nausea, vomiting, breathing difficulty, chest pain, heart failure and possible death.

Naltrexone (revia®, vivitrol™)

Dosing (Adults):
Alcohol dependence
Oral: A dose of 50 mg once daily is recommended for most patients (administer with food or antacids or after meals). The placebo-controlled studies that demonstrated the efficacy of REVIA as an adjunctive treatment of alcoholism used a dose regimen of REVIA 50 mg once daily for up to 12 weeks. Other dose regimens or durations of therapy were not evaluated in these trials. Alt: 25 mg; if no withdrawal signs within 1 hour give another 25 mg; maintenance regimen is flexible, variable and individualized (50 mg/day to 100-150 mg three times per week).

I.M.:: 380 mg once every 4 weeks (Administer I.M. into the upper outer quadrant of the gluteal area. Injection should alternate between the two buttocks.)

A patient is a candidate for treatment with REVIA if:

1) The patient is willing to take a medicine to help with alcohol dependence.
2) The patient is opioid free for 7-10 days.
3) The patient does not have severe or active liver or kidney problems (Typical guidelines suggest liver function tests no greater than 3 times the upper limits of normal, and bilirubin normal.)
4) The patient is not allergic to REVIA , and no other contraindications are present

Opioid antidote (do not give until patient is opioid-free for 7-10 days as required by urinalysis): Oral: 25 mg; if no withdrawal signs within 1 hour give another 25 mg; maintenance regimen is flexible, variable and individualized (50 mg/day to 100-150 mg three times per week).

Supplied:
Injection, powder for suspension [extended-release microspheres]:
Vivitrol™: 380 mg

Tablet: 50 mg
Depade®: 25 mg, 50 mg, 100 mg
ReVia®: 50 mg

Suboxone ®(buprenorphine and naloxone)

Indication: Treatment of opioid dependence. Not recommended for use during the induction period. SUBUTEX or SUBOXONE is administered sublingually as a single daily dose in the range of 12 to 16 mg/day. When taken sublingually, SUBOXONE and SUBUTEX have similar clinical effects and are interchangeable. There are no adequate and well-controlled studies using SUBOXONE as initial medication.
Initial treatment should begin using buprenorphine oral tablets (Subutex). Patients should be switched to the combination product for maintenance and unsupervised therapy.
Maintenance: Target dose (buprenorphine): 16 mg/day (range: 4-24 mg/day.)

Adjusting the dose until the maintenance dose is achieved:
The recommended target dose of SUBOXONE is 16 mg/day. Clinical studies have shown that 16mg of SUBUTEX or SUBOXONE is a clinically effective dose compared with placebo and indicate that doses as low as 12 mg may be effective in some patients. The dosage of SUBOXONE should be progressively adjusted in increments / decrements of 2mg or 4mg to a level that holds the patient in treatment and suppresses opioid withdrawal effects. This is likely to be in the range of 4mg to 24mg per day depending on the individual.

Supplied: sublingual tablet: Buprenorphine 2 mg and naloxone 0.5 mg; buprenorphine 8 mg and naloxone 2 mg.

Drug UPDATES: ZUBSOLV ® (buprenorphine and naloxone ) sublingual tablets
[Drug information / PDF]
Dosing: Click (+) next to Dosage and Administration section (drug info link)

Initial U.S. Approval: 2013

Mechanism of Action: ZUBSOLV sublingual tablet contains buprenorphine and naloxone. Buprenorphine is a partial agonist at the mu-opioid receptor and an antagonist at the kappa-opioid receptor. Naloxone is a potent antagonist at mu-opioid receptors and produces opioid withdrawal signs and symptoms, if administered parenterally, in individuals physically dependent on full opioid agonists.

INDICATIONS AND USAGE: ZUBSOLV sublingual tablet is indicated for treatment of opioid dependence and should be used as part of a complete treatment plan to include counseling and psychosocial support.

Under the Drug Addiction Treatment Act (DATA) codified at 21 U.S.C. 823(g), prescription use of this product in the treatment of opioid dependence is limited to physicians who meet certain qualifying requirements, and who have notified the Secretary of Health and Human Services (HHS) of their intent to prescribe this product for the treatment of opioid dependence and have been assigned a unique identification number that must be included on every prescription.

HOW SUPPLIED:
ZUBSOLV sublingual tablet is supplied in five dosage strengths:
buprenorphine/naloxone 1.4 mg/0.36 mg, white, triangular shape, tablets and
buprenorphine/naloxone 2.9 mg/0.71 mg white, D shape tablets
buprenorphine/naloxone 5.7 mg/1.4 mg, white, round shape tablets
buprenorphine/naloxone 8.6 mg/2.1 mg, white, diamond shape tablets
buprenorphine/naloxone 11.4 mg/2.9 mg, white, capsule shape tablets

Varenicline (chantix ® )

CLINICAL PHARMACOLOGY - Mechanism Of Action
Varenicline binds with high affinity and selectivity at α4β2 neuronal nicotinic acetylcholine receptors. The efficacy of CHANTIX in smoking cessation is believed to be the result of varenicline's activity at a sub-type of the nicotinic receptor where its binding produces agonist activity, while simultaneously preventing nicotine binding to α4β2 receptors.

Electrophysiology studies in vitro and neurochemical studies in vivo have shown that varenicline binds to α4β2 neuronal nicotinic acetylcholine receptors and stimulates receptor-mediated activity, but at a significantly lower level than nicotine. Varenicline blocks the ability of nicotine to activate α4β2 receptors and thus to stimulate the central nervous mesolimbic dopamine system, believed to be the neuronal mechanism underlying reinforcement and reward experienced upon smoking. Varenicline is highly selective and binds more potently to α4β2 receptors than to other common nicotinic receptors (>500-fold α3β4, >3500-fold α7, >20,000-fold α1βγδ), or to non-nicotinic receptors and transporters (>2000-fold). Varenicline also binds with moderate affinity (Ki = 350 nM) to the 5-HT3 receptor

The recommended dose of CHANTIX is 1 mg twice daily following a 1-week titration as follows (CHANTIX should be taken after eating and with a full glass of water.) :
Days 1 – 3: 0.5 mg once daily
Days 4 – 7: 0.5 mg twice daily
Day 8 through End of treatment: 1 mg twice daily

Patients who cannot tolerate adverse effects of CHANTIX may have the dose lowered temporarily or permanently. Patients should be treated with CHANTIX for 12 weeks. For patients who have successfully stopped smoking at the end of 12 weeks, an additional course of 12 weeks treatment with CHANTIX is recommended to further increase the likelihood of long-term abstinence.
Patients who do not succeed in stopping smoking during 12 weeks of initial therapy, or who relapse after treatment, should be encouraged to make another attempt once factors contributing to the failed attempt have been identified and addressed.

WARNING
Serious neuropsychiatric events, including, but not limited to depression, suicidal ideation, suicide attempt and completed suicide have been reported in patients taking CHANTIX. Some reported cases may have been complicated by the symptoms of nicotine withdrawal in patients who stopped smoking. Depressed mood may be a symptom of nicotine withdrawal. Depression, rarely including suicidal ideation, has been reported in smokers undergoing a smoking cessation attempt without medication. However, some of these symptoms have occurred in patients taking CHANTIX who continued to smoke.

All patients being treated with CHANTIX should be observed for neuropsychiatric symptoms including changes in behavior, hostility, agitation, depressed mood, and suicide-related events, including ideation, behavior, and attempted suicide. These symptoms, as well as worsening of pre-existing psychiatric illness and completed suicide have been reported in some patients attempting to quit smoking while taking CHANTIX in the post-marketing experience. When symptoms were reported, most were during CHANTIX treatment, but some were following discontinuation of CHANTIX therapy.

These events have occurred in patients with and without pre-existing psychiatric disease. Patients with serious psychiatric illness such as schizophrenia, bipolar disorder, and major depressive disorder did not participate in the pre-marketing studies of CHANTIX and the safety and efficacy of CHANTIX in such patients has not been established.

Advise patients and caregivers that the patient should stop taking CHANTIX and contact a healthcare provider immediately if agitation, hostility, depressed mood, or changes in behavior or thinking that are not typical for the patient are observed, or if the patient develops suicidal ideation or suicidal behavior. In many post-marketing cases, resolution of symptoms after discontinuation of CHANTIX was reported, although in some cases the symptoms persisted; therefore, ongoing monitoring and supportive care should be provided until symptoms resolve.

The risks of CHANTIX should be weighed against the benefits of its use. CHANTIX has been demonstrated to increase the likelihood of abstinence from smoking for as long as one year compared to treatment with placebo. The health benefits of quitting smoking are immediate and substantial.

DOSING: RENAL IMPAIRMENT
CRCL >/=30 mL/minute: No adjustment required.

CRCL <30 mL/minute: Initiate: 0.5 mg once daily; maximum dose: 0.5 mg twice daily.

Hemodialysis: Maximum dose: 0.5 mg once daily.

Supplied: 0.5mg, 1 mg tablet.

Reference(s)

National Institutes of Health, U.S. National Library of Medicine, DailyMed Database.
Provides access to the latest drug monographs submitted to the Food and Drug Administration (FDA). Please review the latest applicable package insert for additional information and possible updates. A local search option of this data can be found here.