Alkalosis is a term used when the pH in the body is higher than 7.45, and acidosis when the pH is lower than 7.35. Alkalosis and acidosis are thus non-physiological conditions in the body.
There are two types of alkalosis and acidosis –metabolic and respiratory.
Respiratory acidosis or alkalosis arise from changes in pH regulation due to a problem with the respiratory system.
Acidosis and alkalosis which isn’t classified as having a respiratory cause is said to be a metabolic acidosis or alkalosis.
Respiratory acidosis is the most common explanation of imbalances in the acid-base conditions in the body. These arise when a person breathes shallowly or when gas exchange in the lungs is impaired (such as in chronic bronchitis and various pathological other conditions). When this occurs, CO2 builds up in the blood, and consequently the pH decreases.
A typical example when you can get metabolic alkalosis is after severe vomiting (a lot of acid is lost in the vomit) and intake of alkaline substances where HCO3 and other bases are ingested raising the blood levels.