Habit cough

Reflex coughing, as distinct from voluntary or habit coughing, is often associated with unpleasant sensation in the chest or throat however, this is not always present, especially with conditions in the lower airways involving, for example, excessive mucus. The terms used to describe the sensations are various, and include irritation, rawness, and even pain (Widdicombe 2008). 

Codeine, also known as methylmorpliine, C H2 NOt H20, is a colorless white crystalline substance, mp 154.9 C, slightly soluble in water, soluble in alcohol and chloroform, effloresces slowly in dry air. Codeine is derived from opium by extraction or by the methylation of morphine. For medical use, codeine is usually offered as the dichlotide, phosphate, or sulfate. Codeine is habit forming. Codeine is known to exacerbate urticaria (familiarly known as hives). Since codeine is incorporated in numerous prescription medicines for headache, heartburn, fatigue, coughing, and relief of aches and pains, persons with a history of urticaria should make this fact known to their physician. Codeine is sometimes used ill cases of acute pericarditis to relieve severe chest pains in early phases of disease. Codeine is sometimes used in drug therapy of renal (kidney) diseases. 

In 1955, Beecher attempted to quantify the placebo response in 15 randomly selected clinical trials encompassing a wide variety of ailments (e.g., pain, cough, behavior changes).Of the 1082 patients receiving placebo, 35.2% experienced therapeutic benefits.Response was noted regardless of the intelligence of the person. Further, patient beliefs, habits, and educational background appeared to be consistent within those who responded to placebo. ... 

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