Some users report having mind-expanding, mystical experiences while they’re under the influence of LSD. However, because it’s impossible to control the type of experiences you’ll have, the length of your experience or your reactions to the drug – you cannot predict if you are likely to have terrifying hallucinations or pleasant ones. Even worse, these episodes may continue after you’ve stopped using LSD, interfering with your social and professional life and putting you at risk of anxiety, depression and suicide.
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 '.