VA CLASSIFICATION
Primary: AD600
Commonly used brand name(s): Habitrol, NicoDerm CQ, Nicoderm, Nicorette, Nicorette Plus, Nicotrol, Prostep.
Note: For a listing of dosage forms and brand names by country availability, see Dosage Forms section(s).
Category:
Smoking cessation adjunct&mdash,
Indications
Accepted
Nicotine dependence (treatment adjunct)&mdash,Nicotine chewing gum and nicotine transdermal systems are indicated as temporary aids for the cigarette smoker who wants to give up smoking. They serve as alternative sources of nicotine and provide relief of nicotine withdrawal symptoms in nicotine-dependent individuals who are acutely withdrawing from cigarette smoking. <07>4 <07>3 <07>2 <07>1 <07>0 <06>9 <06>8 <06>7 <06>6 <06>5 <06>4 <06>3
&mdash,It is recommended that nicotine chewing gum and transdermal systems be used in conjunction with comprehensive behavior modification programs that include education, counseling, and psychological support.
&mdash,Generally, smokers who have a strong physical nicotine dependence are more likely to benefit from the use of these nicotine products. Smoking withdrawal effects such as irritability, drowsiness, fatigue, headache, and nicotine craving are lessened with their use. <06>2 <06>1 <06>0 <25>9
Acceptance not established
Nicotine, in conjunction with a 5-aminosalicylic acid compound or other conventional maintenance therapy, has been used in the treament of ulcerative colitis to ameliorate the condition and relieve symptoms <25>8 <25>7 <25>6 <25>5 <25>4 <25>3 but not induce remission <25>2 <25>1 in nonsmoking patients with mild to moderate ulcerative colitis. However, there are insufficient data to support the safety and efficacy of nicotine for this use. <25>0 (Evidence rating: I)
Nicotine, in conjunction with an antipsychotic such as haloperidol, has been used in the treatment of Gilles de la Tourette"s syndrome to decrease the severity and frequency of tics and vocalizations of Tourette"s syndrome. <22>9 <22>8 <22>7 <22>6 <22>5 <22>4 <22>3 <22>2 However, there are insufficient data to support the safety and efficacy of nicotine for this use. <22>1 (Evidence rating: II)
Pharmacology/Pharmacokinetics
Physicochemical characteristics:
Source&mdash,
Molecular weight&mdash,
Nicotine: 162.24 <06>6
Ionization constants&mdash,
Mechanism of action/Effect:
Smoking cessation adjunct:
Nicotine acts as an agonist at the nicotinic cholinergic receptors at the autonomic ganglia, <25>9 <25>8 <25>7 <25>6 <25>5 in the adrenal medulla, at neuromuscular junctions, and in the brain. <25>4 <25>3 <25>2 Nicotine's positive reinforcing properties are believed to be the result of the release of neurotransmitters including acetylcholine, beta-endorphin, dopamine, norepinephrine, serotonin, and others that mediate pleasure, arousal, elevated mood, appetite, and other desirable psychological states. <25>1
When the gum is chewed, nicotine is displaced from polacrilex by alkaline saliva. <25>0 <22>9
Other actions/effects:
Has actions on the chemoreceptors of the aortic and carotid bodies, <22>8 <22>7 <22>6 resulting in reflex vasoconstriction, tachycardia, elevated blood pressure, and stimulation of respiration. <22>5 <22>4 <22>3 <22>2 <22>1 <22>0
Stimulates sympathetic ganglia and adrenal medulla, <22>9 causing release of catecholamines, <22>8 <22>7 <22>6 <22>5 resulting in direct sympathomimetic effects on the heart and peripheral vasculature. <22>4
Has actions that tend to reduce blood pressure and heart rate. In low concentrations, stimulates certain chemoreceptors in the pulmonary and coronary circulation, leading to reflex bradycardia and hypotension.
Causes release of antidiuretic hormone (ADH) by stimulation of hypothalamus.
Stimulation of emetic chemoreceptor trigger zone of medulla oblongata and vagal reflex activation may result in vomiting.
Parasympathetic stimulation increases tone and motor activity of the gastrointestinal tract, leading to nausea, vomiting, and occasionally diarrhea.
Effects of nicotine on exocrine glands cause an initial stimulation followed by inhibition of salivary and bronchial secretions.
Action on the central nervous system (CNS) may result in respiratory failure due to both central paralysis and peripheral blockade of muscles of respiration.
Absorption:
Chewing gum:
Buccal mucosa: Absorption enhanced by buffering of gum to pH 8.5, rate of absorption is slower than from lungs during smoking.
Stomach: Not absorbed in significant amounts when gum is swallowed because of poor release of nicotine from gum in acidic pH of stomach. <22>3
Transdermal systems:
Skin: Well absorbed. <22>2 <22>1
The volume of distribution following intravenous administration is approximately 2 to 3 L per kg of body weight. <29>5 <29>4 <29>3
0 comments:
Post a Comment