Symptoms of a high platelet count include headache, bleeding, feeling weak, and numbness in the hands or feet, states Healthgrades. Blood-clotting symptoms, including nausea, seizures, dizziness, difficulty breathing and... More »

Effects of a high blood platelet count, or thrombocytosis, can include stroke, heart attack and blood clots due to blood vessel blockage, according to the Cleveland Clinic. After thrombocytosis has been in an individual'... More »

Typical symptoms of a low blood platelet count include prolonged bleeding from cuts, bleeding from nose or gum, petechiae, unusually heavy menstrual flow and blood in stools or urine, according to Mayo Clinic. This condi... More » Health Pain & Symptoms

Causes of a high platelet count include recent spleen removal, cancer, chronic myelogenous leukemia and the use of certain medications, according to MedlinePlus. An increased platelet count indicates the body is making m... More » Health Medical Ranges & Levels

A high platelet count can be caused by a bone marrow condition that produces too many platelets, a separate disease, or another condition that affects platelet count, according to the National Heart, Lung, and Blood Inst... More » Health Medical Ranges & Levels

An increased platelet count, or thrombocythemia, can cause blood clots that travel to the brain, feet and hands, according to Healthline. The symptoms include numbness in the fingers and toes, dizziness, headache, heart ... More » Health Medical Ranges & Levels

Causes of a high platelet count include cancer, recent spleen removal and anemia caused by premature destruction of the red blood cells, notes MedlinePlus. A normal platelet count ranges from 150,000 to 400,000 platelets... More »