taking out of the equation the marijuana habit - it's not exactly a great idea to put too much smoke from anything into your lungs - the answer to whether or not your friend is hurting herself by coughing so much is yes and no. a somewhat abbreviated answer is that there can be complications from coughing too much or too forcefully some of which can be immediate while others can take place over time. she could potentially cause herself to faint have issues with incontinence (the fancy way of saying she might soil herself) or give herself red eyes. it is also possible to develop hernias lower rib fractures or inflammation of the rib cartilage. i can't say how hard or how often your friend would have to be coughing for any of these problems to arise - and i doubt that any of them are likely to be fatal - they can certainly happen and several would require medical intervention. not to go too far off topic or editorialize but it is possible that your friend is more likely to develop one of these potential side effects while she's high since she at least professes to be in control of how hard she makes herself cough and would be unlikely to stop unless a problem arose first. i can't say for certain that your friend is definitely hurting herself by forcing herself to cough so much but she should know that it is possible.
a friend coughs after every hit when she smokes pot. is there any long term effect of coughing all the time on purpose? . i am told she believes it increases the effectiveness of smoking pot but to me it seems like it would cause problems down the road to cough all the time. even if as in her case it is intentional. she doesn't take what i say seriously because i do not smoke pot and dislike the habit. is she hurting herself by doing this?