Pharmacy/pill for smoking
QUESTION: Could a pill that contains bupropion, mecamylamine, and 18-methoxycoronaridine work to get people to stop smoking? These chemicals would block nicotinic acetylcholine receptors in the brains and would help with some of the symptoms of smoking, but would it be safe/a possibility? Why?
ANSWER: Hello Juliana,
There are a number of products available in the market to help quit smoking, but your question is specifically about the three whose details are given below:
1. Bupropion (Zyban for example)
Bupropion is usually initially prescribed in a dosage of 150 mg twice a day, eventually increasing to 300 mg twice a day. Bupropion can be safely taken for up to a year, and reduces not only the cravings for nicotine but also the irritability and difficulty with concentration that are often part of quitting smoking. The medication may also reduce the tendency for people to overeat while they’re in the process of quitting smoking, which could decrease or avoid the risk of weight gain.
This is a nicotinic receptor antagonist and it does have potential for helping people leave smoking, but the trials on this have not been completed due to shortage of funds. A fresh application for clinical trials has been filed in US on 2/9/2014, and it will be some more time till its results are submitted to FDA and it is cleared for human use.
This is an old drug launched in the 1950s, it is also a nicotinic receptor antagonist, however I very much doubt if any work is being done or will be done on this simply because of its patent status.
There are one or two drugs which help in nicotine addiction, but I am not sure if you want that information, however if you do need it, please let me know.
I hope this information helps you
All the best
---------- FOLLOW-UP ----------
QUESTION: Hi Ravi,
This was very helpful! Thanks for getting back to me so quickly! I would love to hear the information you have about the 2 drugs that help nicotine addiction.
Thanks so much!
I think there was a mess up on this site and my answer to your follow up question did not reach you. Well here it is:
Varenicline (Chantix) has been launched by Pfizer in the US and other countries as an aid to stop smoking. The drug should be started about a week prior to the date that you wish to stop smoking, it reduces the urge to smoke and by about 7 days your need to smoke is so low that you can stop.
Varenicline binds with high affinity and selectivity at neuronal nicotinic acetylcholine receptors. The efficacy of CHANTIX in smoking cessation is believed to be the result of varenicline's activity at α4β2 sub-type of the nicotinic receptor where its binding produces agonist activity, while simultaneously preventing nicotine binding to these receptors.
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.
However the side effects of varenicline on the central nervous system are disturbing and the FDA has warned as follows:
Serious neuropsychiatric events including, but not limited to, depression, suicidal ideation, suicide attempt, and completed suicide have been reported in patients taking CHANTIX.(This is the original warning in brief.)
The alternative to Chantix is nicotine patch, or chewing gum containing nicotine, which has been in the market for quite some time. I would recommend Nicotine gum or patch as compared to Chantix. It is a more logical way to stop smoking.
All the best