4. Lung or heart disease
Aside from asthma, which is a chronic condition that in most cases is suffered from infancy, other lung conditions, or malfunctions that you can get at a later stage of your life can also cause a dry cough. The risk here is that, when there is no other symptom noticed by the person, they might mistakenly believe that the cause of their problem is in their throat itself, or viral infection at most, and the underlying cause remains undetected.
For example, some lung problems such as pneumothorax can cause a dry cough. Pneumothorax happens when the lung collapses, often after an injury, and the body produces a coughing reflex in an attempt to increase breathing capacity. Lung cancer might also cause a dry cough in a number of cases. The vagal reflex that causes the dry cough can also be triggered by heart insufficiency; in this case, it is common to appreciate a pink foam in your spit.