question: Why do long time smokers rarely cough while inhaling, but long time marijuana smokers continue to cough from inhaling ?
comment: Cigarettes contain hundreds if not thousands of chemicals that are there to numb your throat for example methanol. This soothes your throat and lungs so you don't get the irritation. On the other hand marijuana is simply marijuana therefore when you burn it, it irritates the lungs and throat, because your inhaling smoke from burnt organic matter and nothing else
passages: There has been a limited amount of studies that have looked at the effects of smoking cannabis on the respiratory system. Chronic heavy marijuana smoking is associated with coughing, production of sputum, wheezing, coughing, and other symptoms of chronic bronchitis. Regular cannabis use has not been shown to cause significant abnormalities in lung function.
   A limited number of studies have examined the effects of cannabis smoking on the respiratory system. Chronic heavy marijuana smoking is associated with coughing, production of sputum, wheezing, and other symptoms of chronic bronchitis. The available evidence does not support a causal relationship between cannabis use and chronic obstructive pulmonary disease. Short-term use of cannabis is associated with bronchodilation. Other side effects of cannabis use include cannabinoid hyperemesis syndrome.
   Classic lung diseases are a complication of HIV/AIDS with emphysema being a source of disease. HIV is cited as a risk factor for the development of emphysema regardless of smoking status. HIV associated emphysema occurs over a much shorter time than that associated with smoking. It is thought that an understanding of the mechanisms that underlie the triggering of HIV associated emphysema may help in the understanding of the mechanisms of the development of smoking-related emphysema.
  
  Section::::By location.:Lungs.:Ritalin lung.
   Developing a chronic cough can occur from different life style choices. These include smoking cigarettes that the individual smokes themselves or breathes from second-hand exposure. Long-term exposure to smoke can irritate airways and lead to chronic cough and in severe cases lung damage. Other risk-factors include exposure to the air. Individuals that work in factories or laboratories that deal with chemicals have a chance of developing chronic cough from long term exposure.
  
  Section::::Mechanism.
   The prevalence of cough in many communities in Europe and USA is 9–33% of the population. Chronic cough is more common in those who smoke by threefold compared to people who never smoke. Data analysis shows that exposure to tobacco smoke in a home environment is a risk factor for children due to second hand smoke inhalation. Other causes of chronic cough include higher PM10 concentrations have been related to increase cough and sore throat in children. An increase in nitrogen dioxide has also show a rising association with chronic cough syndrome.
  
  Section::::Children.
   Cannabis (marijuana) can be smoked in a variety of pipe-like implements made in different shapes and of different materials including hand pipes ("bowls"), water pipes ("bongs"), cigarettes ("joints"), or blunts. When smoking a joint or blunt with someone else or a group of people, it is common courtesy to take no more than two inhalations ("puffs", "pulls", "tokes", "hits", "rips") then pass it on. With a pipe, bowl, bong, or vaporizer, one inhalation is the norm.
  
  Section::::Smoking methods.:Joint.
   BULLET::::- Chronic bronchitis, an inflammation in the major airways such as the bronchial tubules that causes the coughing of coloured sputum. Most carriers of chronic bronchitis have a history of smoking. Due to the nature of chronic bronchitis, it is on a spectrum of smoking-related lung disease also known as chronic obstructive pulmonary disease. Because of this spectrum, other lung diseases on the spectrum such as emphysema can co-exist with COPD. It accounts for 5% of chronic cough.
   BULLET::::- Experiment on smoking correlations: In 2002, an experiment was done and published by the American College of Chest Physicians to find if there was a correlation of smokers with coughing and phlegm. In the study, 117 participants were studied, a mix of current smokers, ex-smokers, non-smokers, and a positive control of participants with a disease, COPD (Chronic Obstructive Pulmonary Disease.) At the end of the experiment, experimenters found that there was a high correlation between phlegm and cough with smoking of 0.49 (p  0.001.)
   Regular cannabis smokers show pathological changes in lung cells similar to those that precede the development of lung cancer in tobacco smokers. Gordon and colleagues in a 2013 literature review said: "Unfortunately, methodological limitations in many of the reviewed studies, including selection bias, small sample size, limited generalizability, and lack of adjustment for tobacco smoking, may limit the ability to attribute cancer risk solely to marijuana use." Reviewing studies adjusted for age and tobacco use, they said there was a risk of lung cancer even after adjusting for tobacco use, but that the period of time over which the risk increases is uncertain.
   Smoking cannabis has been linked to adverse respiratory effects including: chronic coughing, wheezing, sputum production, and acute bronchitis. It has been suggested that the common practice of inhaling cannabis smoke deeply and holding breath could lead to pneumothorax. In a few case reports involving immunocompromised patients, pulmonary infections such as aspergillosis have been attributed to smoking cannabis contaminated with fungi. The transmission of tuberculosis has been linked to cannabis inhalation techniques, such as sharing water pipes and 'Hotboxing'.
  
  Section::::Physical health.:Reproductive and endocrine effects.
   Section::::Physical health.:Cancer.:Lung.
  
  There have been a limited number of studies that have looked at the effects of smoking cannabis on the respiratory system. Chronic heavy cannabis smoking is associated with coughing, production of sputum, wheezing, and other symptoms of chronic bronchitis. Regular cannabis use has not been shown to cause significant abnormalities in lung function.
   Cannabis smoke contains thousands of organic and inorganic chemical compounds. This tar is chemically similar to that found in tobacco smoke, and over fifty known carcinogens have been identified in cannabis smoke, including; nitrosamines, reactive aldehydes, and polycylic hydrocarbons, including benz[a]pyrene. Cannabis smoke is also inhaled more deeply than tobacco smoke. , there is no consensus regarding whether cannabis smoking is associated with an increased risk of cancer. Light and moderate use of cannabis is not believed to increase risk of lung or upper airway cancer. Evidence for causing these cancers is mixed concerning heavy, long-term use. In general there are far lower risks of pulmonary complications for regular cannabis smokers when compared with those of tobacco. A 2015 review found an association between cannabis use and the development of testicular germ cell tumors (TGCTs), particularly non-seminoma TGCTs. A 2015 analysis of six studies found little evidence that long-term or regular cannabis smoking was associated with lung cancer risk, though it could not rule out whether an association with heavy smoking exists. Another 2015 meta-analysis found no association between lifetime cannabis use and risk of head or neck cancer. Combustion products are not present when using a vaporizer, consuming THC in pill form, or consuming cannabis foods.
   A 2013 literature review by Gordon and colleagues concluded that inhaled cannabis is associated with lung disease, although Tashkin's 2013 review has found "no clear link to chronic obstructive pulmonary disease".
  
  Of the various methods of cannabis consumption, smoking is considered the most harmful; the inhalation of smoke from organic materials can cause various health problems (e.g., coughing and sputum). Isoprenes help to modulate and slow down reaction rates, contributing to the significantly differing qualities of partial combustion products from various sources.
   Asthma, COPD, and smokers have reduced airflow ability. People who suffer from asthma and COPD show decreases in exhaled air due to inflammation of the airways. This inflammation causes narrowing of the airways which allows less air to be exhaled. Numerous things cause inflammation some examples are cigarette smoke and environmental interactions such as allergies, weather, and exercise. In smokers the inability to exhale fully is due to the loss of elasticity in the lungs. Smoke in the lungs causes them to harden and become less elastic, which prevents the lungs from expanding or shrinking as they normally would.
   In 2013 the International Lung Cancer Consortium found no significant additional lung cancer risk in tobacco users who also smoked cannabis. Nor did they find an increased risk in cannabis smokers who did not use tobacco. They concluded that "[o]ur pooled results showed no significant association between the intensity, duration, or cumulative consumption of cannabis smoke and the risk of lung cancer overall or in never smokers." They cautioned that "[o]ur results cannot preclude the possibility that cannabis may exhibit an association with lung cancer risk at extremely high dosage."
   Some data on the correlation of an increase in the incidence of lung cancer and cannabis smoking are conflicting. A systematic review evaluating 19 studies from 1966 to 2006 found no significant tobacco-adjusted association between cannabis smoking and lung cancer development despite evidence of precancerous histopathologic changes of the respiratory mucosa. 
  
  Cannabis smoke was listed as a cancer agent in California in 2009. Cannabis smoke contains many of the same carcinogens as tar from tobacco smoke.
   According to the Nurses' Health Study, the risk of pulmonary adenocarcinoma increases substantially after a long duration of tobacco smoking: smokers with a previous smoking duration of 30–40 years are more than twice as likely to develop lung adenocarcinoma compared to never-smokers (relative risk of approximately 2.4); a duration of more than 40 years increases relative risk to 5.
   Section::::Signs and symptoms.:Other symptoms.
  
  In COPD, breathing out may take longer than breathing in. Chest tightness may occur, but is not common and may be caused by another problem. Those with obstructed airflow may have wheezing or decreased sounds with air entry on examination of the chest with a stethoscope. A barrel chest is a characteristic sign of COPD, but is relatively uncommon. Tripod positioning may occur as the disease worsens.
   A 2007 study found that while tobacco and cannabis smoke are quite similar, cannabis smoke contained higher amounts of ammonia, hydrogen cyanide, and nitrogen oxides, but lower levels of carcinogenic polycyclic aromatic hydrocarbons (PAHs). This study found that directly inhaled cannabis smoke contained as much as 20 times as much ammonia and 5 times as much hydrogen cyanide as tobacco smoke and compared the properties of both mainstream and sidestream (smoke emitted from a smouldering 'joint' or 'cone') smoke. Mainstream cannabis smoke was found to contain higher concentrations of selected polycyclic aromatic hydrocarbons (PAHs) than sidestream tobacco smoke. However, other studies have found much lower disparities in ammonia and hydrogen cyanide between cannabis and tobacco, and that some other constituents (such as polonium-210, lead, arsenic, nicotine, and tobacco-specific nitrosamines) are either lower or non-existent in cannabis smoke.
   To simulate environmental tobacco smoke, scientists expose animals to sidestream smoke, that which emanates from the cigarette's burning cone and through its paper, or a combination of mainstream and sidestream smoke. The IARC monographs conclude that mice with prolonged exposure to simulated environmental tobacco smoke, that is 6hrs a day, 5 days a week, for five months with a subsequent 4 month interval before dissection, will have significantly higher incidence and multiplicity of lung tumors than with control groups.
  
  The IARC monographs concluded that sidestream smoke condensates had a significantly higher carcinogenic effect on mice than did mainstream smoke condensates.
   In another study performed with non-smoking patients, it demonstrates that oral administration of "Passifora incarnata" following extubation for patients surgery reduced the patients coughing versus the control group. By administering "Passiflora incarnata" orally with the correct dosage, it can result in antitussive activities without impairing the patient drastically. The results presented show a decrease of post extubation cough after out-patient surgery but it was only recorded early on. With this information, further research can be applied to create other medications for coughing but the authors note the limitations on the study included short observation period as well as a small sample size.
   However, a 2000 NORML-MAPS cannabis study found that "water pipes filter out more psychoactive THC than they do other tars, thereby requiring users to smoke more to reach their desired effect". In the study, smoke from cannabis supplied by the NIDA was drawn through a number of smoking devices and analyzed. This study looked at the tar to cannabinoid ratio in the gas in output by various bongs, as well as unfiltered and filtered joints, and vaporizers. The results showed that only vaporizers produced a better tar to cannabinoid ratio than unfiltered joints, but that within the cannabinoids produced, even vaporizers warped the ratio of THC (the psychoactive component of the smoke) to CBN (capable of producing medical benefits but is not psychoactive) in favor of CBN. This showed an unfiltered joint had the best tar to THC ratio of all, and bongs were actually seriously detrimental in this respect.
   Cannabis smoke contains thousands of organic and inorganic chemical compounds. This tar is chemically similar to that found in tobacco smoke, and over fifty known carcinogens have been identified in cannabis smoke, including nitrosamines, reactive aldehydes, and polycylic hydrocarbons, including benz[a]pyrene. Light and moderate use of cannabis is not believed to increase risk of lung or upper airway cancer. Evidence for causing these cancers is mixed concerning heavy, long-term use. In general there are far lower risks of pulmonary complications for regular cannabis smokers when compared with those of tobacco. Combustion products are not present when using a vaporizer, consuming THC in pill form, or consuming cannabis edibles.
   Section::::Research.
  
  In 1996, Celermajer published a study showing that exposure to secondhand smoke was associated with "dose-related impairment of endothelium-dependent dilatation" in the arteries of healthy young adults.
  
  Section::::Honors and awards.
   Whether or not smoking affects the progression or incidence of flock worker's lung is a topic of ongoing research as of 2015. Research in rats has shown that nylon flocking is a causative agent.
  
  Section::::Diagnosis.
  