A substitute or substitute good in economics and consumer theory is a product or service that a consumer sees as the same or similar to another product.
Postural orthostatic tachycardia syndrome (POTS) is one of a group of disorders that have orthostatic intolerance (OI) as their primary symptom.OI describes a condition in which an excessively reduced volume of blood returns to the heart after an individual stands up from a lying down position.n POTS, the lightheadedness or fainting is also accompanied by a rapid increase in heartbeat of more than 30 beats per minute, or a heart rate that exceeds 120 beats per minute, within 10 minutes of rising. The faintness or lightheadedness of POTS are relieved by lying down again.
Sicca syndrome: WHAT: Keratoconjunctivitis sicca. Keratoconjunctivitis Sicca (KCS): an eye condition in which there is decreased tear production and inflammation of the cornea and conjunctiva.WHY: Keratoconjunctivitis sicca is found in a significant number of patients with rheumatoid arthritis.CS plus xerostomia is called the sicca syndrome. The association of the sicca syndrome with rheumatoid arthritis is known as Sjogren's syndrome. HOW: Clinically, patients with KCS may present with itching, burning eyes.