Low blood sugar may interfere with the functions of the muscles and brain cells. Hyperparathyroidism can cause fatigue and weakness, increased thirst, impaired thinking, and bone fractures. Myelodysplastic syndromes are diseases that affect the bone marrow and blood, causing anemia and tiredness. Hypopituitarism is a rare disorder of the pituitary glands, which can cause many different symptoms. Flushed skin occurs when the hundreds of tiny blood vessels just beneath the skin dilate, or widen. WebMD does not provide medical advice, diagnosis or treatment. However, recognizing the early signs can significantly improve a person’s…, Testicular cancer is a relatively rare type of cancer that affects the testicles. Enter the shape, color, or imprint of your prescription or OTC drug. Heat exposure can cause dizziness, nausea, headache, weakness, a fast heartbeat, muscle cramps, and more. A chemical burn can cause symptoms ranging from burning and blisters to pain and shortness of breath. Low blood sugar can have serious consequences. Enter the shape, color, or imprint of your prescription or OTC drug. Fight allergies with daily forecasts, local alerts, and personalized tips. Here, doctors explain why you might feel lightheaded—from low blood sugar to … The American Diabetes Association (ADA) recommends getting between 15 and 20 grams (g) of sugars or carbohydrates with each snack, and between 40 and 65 g at each meal. "Going long periods of time without eating, especially after physical activity, is one of the main reasons for drops in blood sugar levels. Get organized and track baby's weekly development. Heat exhaustion causes intense thirst, heavy sweating, pale, cool, and moist skin, muscle cramps, and more. Emphysema is a chronic lung condition that causes shortness of breath, a chronic cough, wheezing, and more. Other symptoms include itching of the eyes, nose, mouth, and throat, low blood pressure, and a rapid heart rate. Mononucleosis is a viral infection causing extreme fatigue, sore throat, fever, rash, muscle aches, and more. When the body produces too much or too little of a hormone, this disrupts its internal communication. People often refer to this type of flushed skin as blushing. West Nile virus is an infection spread by mosquitoes, and can cause diarrhea, fever, abdominal pain, and more. When sugar levels in the blood drop too low, the condition is known as hypoglycemia. Low blood sugar, or low glucose levels, causes shakiness, anxiety, clammy skin, irritability, hunger, and more. Hypothyroidism your body functions slow down, making you gain weight and feel tired all the time. This effect is more noticeable in regions of the body where the blood vessels are closest to the skin, such as the cheeks and chest. Rosacea is a long-term skin condition that usually occurs on the face and can cause redness, pimples, visible blood vessels, and other skin problems. The Ultimate Guide to Health and Happiness, High-Dose Biotin Fails MS Trial, Dashing Hopes, Over Half of American Adults With Advanced MS Experience Mistreatment by Caregiver, Survey Shows, Tippi Coronavirus: Tips for Living With COVID-19. By Caroline Bellamy Updated: 16:57 EST, 9 August 2008. Heat exposure can cause dizziness, nausea, headache, weakness, a fast heartbeat, muscle cramps, and more. Mast cells are part of the immune system, and MCAS occurs when the body releases too much of the substances inside these cells at the wrong times. Sometimes, flushing can be a sign of an underlying medical condition, such as rosacea, cancer, or an endocrine disorder. However, people who are feeling too hot should ensure that they drink some water and focus on taking deep breaths. MNT is the registered trade mark of Healthline Media. Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more. The links below will provide you with more detailed information on these medical conditions from the WebMD Symptom Checker and help provide a better understanding of causes and treatment of these related conditions. Low blood pressure, or hypotension, can make you feel lightheaded and dizzy.