Bupropion HCl, Naltrexone HCl
Indications
Bupropion HCl, Naltrexone HCl is used for:
Bupropion
Bupropion is indicated for the treatment of major depressive disorder (MDD), seasonal affective disorder (SAD), and as an aid to smoking cessation. When used in combination with [naltrexone] as the marketed product Contrave?, bupropion is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management in adults with an initial body mass index (BMI) of: B30 kg/m^2 or greater (obese) or B27 kg/m^2 or greater (overweight) in the presence of at least one weight-related comorbid condition (e.g., hypertension, type 2 diabetes mellitus, or dyslipidemia). Bupropion is also used off-label as a first-line treatment in patients with ADHD and comorbid bipolar disorder when used as an adjunct to mood stabilizers.[F4624]
Naltrexone
Used as an adjunct to a medically supervised behaviour modification program in the maintenance of opiate cessation in individuals who were formerly physically dependent on opiates and who have successfully undergone detoxification. Also used for the management of alcohol dependence in conjunction with a behavioural modification program.
Bupropion is indicated for the treatment of major depressive disorder (MDD), seasonal affective disorder (SAD), and as an aid to smoking cessation. When used in combination with [naltrexone] as the marketed product Contrave?, bupropion is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management in adults with an initial body mass index (BMI) of: B30 kg/m^2 or greater (obese) or B27 kg/m^2 or greater (overweight) in the presence of at least one weight-related comorbid condition (e.g., hypertension, type 2 diabetes mellitus, or dyslipidemia). Bupropion is also used off-label as a first-line treatment in patients with ADHD and comorbid bipolar disorder when used as an adjunct to mood stabilizers.[F4624]
Naltrexone
Used as an adjunct to a medically supervised behaviour modification program in the maintenance of opiate cessation in individuals who were formerly physically dependent on opiates and who have successfully undergone detoxification. Also used for the management of alcohol dependence in conjunction with a behavioural modification program.
Adult Dose
Child Dose
Renal Dose
Administration
Contra Indications
Precautions
Pregnancy-Lactation
Interactions
Adverse Effects
Side effects of Bupropion HCl, Naltrexone HCl :
Mechanism of Action
Bupropion
Bupropion is a norepinephrine/dopamine-reuptake inhibitor (NDRI) that exerts its pharmacological effects by weakly inhibiting the enzymes involved in the uptake of the neurotransmitters norepinephrine and dopamine from the synaptic cleft, therefore prolonging their duration of action within the neuronal synapse and the downstream effects of these neurotransmitters. More specifically, bupropion binds to the norepinephrine transporter (NET) and the dopamine transporter (DAT).[A6399,A178810] Bupropion was originally classified as an "atypical" antidepressant because it does not exert the same effects as the classical antidepressants such as Monoamine Oxidase Inhibitors (MAOIs), Tricyclic Antidepressants (TCAs), or Selective Serotonin Reuptake Inhibitors (SSRIs). While it has comparable effectiveness to typical first-line options for the treatment of depression such as SSRIs,[A178798,A178804] bupropion is a unique option for the treatment of MDD as it lacks any clinically relevant serotonergic effects, typical of other mood medications, or any effects on histamine or adrenaline receptors.[A6399,A198804] Lack of activity at these receptors results in a more tolerable side effect profile; bupropion is less likely to cause sexual side effects, sedation, or weight gain as compared to SSRIs or TCAs, for example.[A178804,A178807] When used as an aid to smoking cessation, bupropion is thought to confer its anti-craving and anti-withdrawal effects by inhibiting dopamine reuptake, which is thought to be involved in the reward pathways associated with nicotine, and through the antagonism of the nicotinic acetylcholinergic receptor (AChR), thereby blunting the effects of nicotine.[A178825,A1966,A16508] Furthermore, the stimulatory effects produced by bupropion in the central nervous system are similar to nicotine's effects, making low doses of bupropion a suitable option as a nicotine substitute.[A179062] When used in combination with [naltrexone] in the marketed product Contrave? for chronic weight management, the two components are thought to have effects on areas of the brain involved in the regulation of food intake. This includes the hypothalamus, which is involved in appetite regulation, and the mesolimbic dopamine circuit, which is involved in reward pathways.[L6562] Studies have shown that the combined activity of bupropion and [naltrexone] increase the firing rate of hypothalamic pro-opiomelanocortin (POMC) neurons and blockade of opioid receptor-mediated POMC auto-inhibition, which are associated with a reduction in food intake and increased energy expenditure.[L6562,A179038,A179050] This combination was also found to reduce food intake when injected directly into the ventral tegmental area of the mesolimbic circuit in mice, which is an area associated with the regulation of reward pathways.[L6562]
Naltrexone
Naltrexone is a pure opiate antagonist and has little or no agonist activity. The mechanism of action of naltrexone in alcoholism is not understood; however, involvement of the endogenous opioid system is suggested by preclinical data. Naltrexone is thought to act as a competitive antagonist at mc, ?, and d receptors in the CNS, with the highest affintiy for the ŵ receptor. Naltrexone competitively binds to such receptors and may block the effects of endogenous opioids. This leads to the antagonization of most of the subjective and objective effects of opiates, including respiratory depression, miosis, euphoria, and drug craving. The major metabolite of naltrexone, 6-�V-naltrexol, is also an opiate antagonist and may contribute to the antagonistic activity of the drug.
Bupropion is a norepinephrine/dopamine-reuptake inhibitor (NDRI) that exerts its pharmacological effects by weakly inhibiting the enzymes involved in the uptake of the neurotransmitters norepinephrine and dopamine from the synaptic cleft, therefore prolonging their duration of action within the neuronal synapse and the downstream effects of these neurotransmitters. More specifically, bupropion binds to the norepinephrine transporter (NET) and the dopamine transporter (DAT).[A6399,A178810] Bupropion was originally classified as an "atypical" antidepressant because it does not exert the same effects as the classical antidepressants such as Monoamine Oxidase Inhibitors (MAOIs), Tricyclic Antidepressants (TCAs), or Selective Serotonin Reuptake Inhibitors (SSRIs). While it has comparable effectiveness to typical first-line options for the treatment of depression such as SSRIs,[A178798,A178804] bupropion is a unique option for the treatment of MDD as it lacks any clinically relevant serotonergic effects, typical of other mood medications, or any effects on histamine or adrenaline receptors.[A6399,A198804] Lack of activity at these receptors results in a more tolerable side effect profile; bupropion is less likely to cause sexual side effects, sedation, or weight gain as compared to SSRIs or TCAs, for example.[A178804,A178807] When used as an aid to smoking cessation, bupropion is thought to confer its anti-craving and anti-withdrawal effects by inhibiting dopamine reuptake, which is thought to be involved in the reward pathways associated with nicotine, and through the antagonism of the nicotinic acetylcholinergic receptor (AChR), thereby blunting the effects of nicotine.[A178825,A1966,A16508] Furthermore, the stimulatory effects produced by bupropion in the central nervous system are similar to nicotine's effects, making low doses of bupropion a suitable option as a nicotine substitute.[A179062] When used in combination with [naltrexone] in the marketed product Contrave? for chronic weight management, the two components are thought to have effects on areas of the brain involved in the regulation of food intake. This includes the hypothalamus, which is involved in appetite regulation, and the mesolimbic dopamine circuit, which is involved in reward pathways.[L6562] Studies have shown that the combined activity of bupropion and [naltrexone] increase the firing rate of hypothalamic pro-opiomelanocortin (POMC) neurons and blockade of opioid receptor-mediated POMC auto-inhibition, which are associated with a reduction in food intake and increased energy expenditure.[L6562,A179038,A179050] This combination was also found to reduce food intake when injected directly into the ventral tegmental area of the mesolimbic circuit in mice, which is an area associated with the regulation of reward pathways.[L6562]
Naltrexone
Naltrexone is a pure opiate antagonist and has little or no agonist activity. The mechanism of action of naltrexone in alcoholism is not understood; however, involvement of the endogenous opioid system is suggested by preclinical data. Naltrexone is thought to act as a competitive antagonist at mc, ?, and d receptors in the CNS, with the highest affintiy for the ŵ receptor. Naltrexone competitively binds to such receptors and may block the effects of endogenous opioids. This leads to the antagonization of most of the subjective and objective effects of opiates, including respiratory depression, miosis, euphoria, and drug craving. The major metabolite of naltrexone, 6-�V-naltrexol, is also an opiate antagonist and may contribute to the antagonistic activity of the drug.