# What are the symptoms of carcinoid syndrome and how does it affect the body? Canonical page: https://clinicsjo.com/en/faq/ma-hi-a3rad-al-mutalazima-alsartawiya Language: en Category: oncology Publisher: ClinicsJo Published: 2026-09-13T17:52:52.735Z Content updated: 2026-09-13T17:52:52.735Z Translation (ar): https://clinicsjo.com/ar/faq/ma-hi-a3rad-al-mutalazima-alsartawiya Carcinoid syndrome presents as a complex medical condition resulting from the release of excessive amounts of biologically active hormones and chemicals by carcinoid tumors. This syndrome primarily occurs when these tumors spread to the liver or outside the digestive system, as liver enzymes fail to neutralize the secreted hormones, allowing them to enter the bloodstream and cause various systemic symptoms that vary in severity and frequency from one patient to another [\[1\]](). ## Mechanism of Symptoms In normal cases, the liver breaks down hormones produced by the endocrine cells of the digestive system. However, when a neuroendocrine tumor extends to the liver or other parts of the body, these hormones—most notably serotonin—are released into the general circulation without sufficient hepatic processing. This hormonal excess is directly responsible for the clinical symptoms observed by the patient, which may appear as sudden episodes [\[1\]]() [\[2\]](). ## Common Symptoms of Carcinoid Syndrome Symptoms vary depending on the location of the tumor and hormone levels in the blood. Among the most notable clinical signs identified are: - **Flushing of the face and neck:** This is considered one of the most characteristic symptoms, where the patient feels sudden warmth and redness in the face, neck, and sometimes the chest, which may last for several minutes or hours [\[1\]](). - **Digestive disturbances:** Chronic diarrhea is a very common symptom and may be accompanied by abdominal pain, cramps, or a feeling of bloating and fullness, which sometimes leads to malnutrition or unexplained weight loss [\[1\]]() [\[2\]](). - **Breathing problems:** Patients may suffer from episodes of wheezing or shortness of breath similar to asthma symptoms, as a result of the hormones' effect on the smooth muscles in the airways [\[1\]](). - **Cardiovascular symptoms:** The patient may notice a rapid heart rate (palpitations). In some cases, a sudden drop in blood pressure may occur, causing feelings of dizziness, weakness, or confusion [\[1\]]() [\[2\]](). ## Diagnostic Challenges Because the symptoms of carcinoid syndrome, such as diarrhea or abdominal pain, are general and mimic many other common diseases like irritable bowel syndrome or food allergies, diagnosis may be delayed. Therefore, physicians rely on specialized tests to measure hormone levels or their metabolic products, such as the 24-hour urine 5-hydroxyindoleacetic acid (5-HIAA) test, in addition to imaging tests to determine the location and extent of primary tumors [\[1\]]() [\[2\]](). ## When to See a Doctor? If you suffer from recurrent episodes of unexplained flushing, persistent diarrhea that does not respond to standard treatments, or shortness of breath that does not go away, it is essential to undergo a comprehensive medical evaluation. Carcinoid tumors require a careful treatment approach, and you can view more details about care and diagnostic pathways in our article on [Carcinoid Tumors: Diagnosis and Multidisciplinary Treatment (Arabic)](). Remember that early diagnosis and engaging with a specialized medical team play a pivotal role in managing symptoms and improving quality of life; self-diagnosis should not be relied upon due to the complexity of this medical condition and its overlap with other diseases [\[1\]](). ## Medical references - [Gastrointestinal Neuroendocrine Tumors Treatment (PDQ®)–Patient Version]() - [Childhood Gastrointestinal Neuroendocrine Tumors (PDQ®)–Patient Version]() General health education; not a substitute for individualized clinical assessment. Citation URL: https://clinicsjo.com/en/faq/ma-hi-a3rad-al-mutalazima-alsartawiya#answer