Gastrin Test

The gastrin test is a blood test that measures the level of the hormone called gastrin in the blood. Gastrin is a hormone which is responsible for secretion of gastric acid aka hydrochloric acid by the stomach. When there has been an intake of food, gastrin is released into the blood. This causes secretion of gastric acid in the stomach. When the acid level of stomach increases, the body produces less gastrin. A gastrin test is conducted when the person is suffering from conditions like diarrhoea, abdominal pain and peptic ulcers. Medicines or antacids used to treat heartburn may also cause gastrin levels to spike up.

It is recommended that you wear a shirt wherein your arm is exposed for easy withdrawal of blood. The dietary restrictions require you to not drink alcohol for 24 hours before the test. Do not eat for 12 hours before the test. You are also advised not to intake caffeine containing food (like coffee) for 12 hours before the test. Do not chew gum or smoke cigarettes for 4 hours before the test. Certain medications also affect the test results. Talk to your doctor regarding the medications you take. Stress also affects the gastrin levels in the body. You may be asked to lie down quietly for about 30 minutes before the test.

The gastrin test is used to detect the excess levels of gastrin and gastric acid in the body. It is also used to monitor for recurrence of tumour, following the surgical removal of gastrinoma. The test helps understand reason for recurrent peptic ulcer. It is also used for the diagnosis of gastrin producing tumours called gastrinomas. This condition is known as Zollinger-Ellison (ZE) syndrome. It helps identify pernicious anaemia. A higher than normal level of gastrin in the blood also indicates long term gastritis.

A few millilitres of blood sample will be obtained directly from your arm. An elastic band is wrapped around your arm to make the veins swell with blood. The site to be injected is cleansed with antiseptic. The needle is inserted into the vein and a tube attached to the needle is then filled up with blood. Once the required amount of blood has been withdrawn, the needle is removed. A gauze pad or cotton ball is placed over the punctured area as the needle is removed. The sample is transferred to the laboratory for further examination.