What is the first thing that happens when body temperature increases above normal body temperature ?\?
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Having a fever means your body temperature is higher than normal. Something inside your body, such as an infection, has caused your temperature to rise. When you have a fever, your body temperature rises above 37.5C (99.5F). This usually means there is something wrong somewhere. A part of the brain called the hypothalamus controls your body temperature. Normally, the hypothalamus keeps the temperature of the inside of your body at around 37C
(98.6F). This can vary depending on the time of day and what you're doing. But generally, it stays around 36.5 and 37C. Fever is a common symptom in people with all types of cancers. It can be very uncomfortable and cause a lot of concern for you and those looking after you. If you have cancer and develop symptoms of a fever or infection it might be nothing, but it could be a sign of a very serious infection. What to do If you're having cancer
treatment and your temperature goes above 37.5C call your advice line straight away. You should have a number to call them on 24 hours a day. The earlier an infection or fever is treated, the less likely it's that you will have more serious complications. It's very important to find out what is causing the fever so that it can be treated quickly and in the best possible way. The 3 phases of feverFever is your body’s way of letting you know something is wrong. In a way, the fever is helping to fight off your infection. This happens in 3 phases. Your body reacts and heats upYour blood and lymphatic system make white blood cells, which fight infection. When you have an infection, you make lots of these cells. They work faster to try and fight off the infection. The increase in these white blood cells affects your hypothalamus. This makes your body heat up, causing a fever. In the early stages of a fever, you often feel cold and start to shiver. This is your body’s response to a rising temperature. The blood vessels in your skin tighten up (constrict), forcing blood from the outer layer of your skin to inside your body where it is easier to keep the heat in. The outer skin layer then becomes cool and your muscles start to contract. This makes you shiver. Shivering produces more heat and raises your temperature even more. The fever levels offIn the second phase of a fever, the amount of heat you make and lose is the same. So the shivering stops and your body remains at its new high temperature. Cooling downYour body starts to try and cool down so that your temperature can return to normal. The blood vessels in the skin open again, so blood moves back to these areas. You sweat which helps to cool the skin, this helps to cool down the body. This phase of a fever may or may not happen naturally. You may need to have some medication to start it off, as well as treating the underlying cause of the fever. Who is most at risk of having complicationsThe very young and elderly are more likely to get complications from a fever. In the elderly the hypothalamus does not work as well as it does in the young. The body temperature can rise too much, causing heart problems and confusion. Children under 6 might have a fit (seizure) if their temperature gets too high. But in most people, the cause of the fever, such as infection, is more likely to cause problems than the fever itself. Peter Nalin, associate professor of clinical family medicine and director of the family practice residency program at Indiana University, explains. Fever is an elevated temperature of the human body that is substantially beyond the normal range. Normal body temperature fluctuates daily from about one degree below 98.6 degrees Fahrenheit to one degree above that number. Lower body temperatures usually occur before dawn; higher temperatures in the afternoon. Body temperature also varies slightly depending on where on the human body it is measured. Rectal (internal) temperature tends normally to be higher than skin (surface) temperature. Oral and armpit temperatures can approximate actual body temperature and are more convenient to measure. The presence of a fever is usually related to stimulation of the body's immune response. Fever can support the immune system's attempt to gain advantage over infectious agents, such as viruses and bacteria, and it makes the body less favorable as a host for replicating viruses and bacteria, which are temperature sensitive. Infectious agents are not the only causes of fever, however. Amphetamine abuse and alcohol withdrawal can both elicit high temperatures, for example. And environmental fevers--such as those associated with heat stroke and related illnesses--can also occur. The hypothalamus, which sits at the base of the brain, acts as the body's thermostat. It is triggered by floating biochemical substances called pyrogens, which flow from sites where the immune system has identified potential trouble to the hypothalamus via the bloodstream. Some pyrogens are produced by body tissue; many pathogens also produce pyrogens. When the hypothalamus detects them, it tells the body to generate and retain more heat, thus producing a fever. Children typically get higher and quicker fevers, reflecting the effects of the pyrogens upon an inexperienced immune system. Should one eat little or nothing while feverish, as the saying "Feed a cold, starve a fever" suggests? Yes. The reasons for this are threefold. First, during fever, all the body's functions are occurring amidst increased physiologic stress. Provoking digestion during physiologic stress over stimulates the parasympathetic nervous system when the sympathetic nervous system is already active. Second, it is possible that the body could misinterpret some substances absorbed from the gut as allergens during a fever. Finally, excessive fever can, on rare occasions, cause seizures, collapse and delirium--all of which may be further complicated by recent eating. Fever can help fight infection, but sometimes it can climb too high for the body's own good. Internal body temperatures in excess of 105 degrees F, for instance, expose proteins and body fats to direct temperature stressors. This form of heat distress can threaten the integrity and function of proteins accustomed to the body's usual temperature variations and the occasional less excessive fevers. Cellular stress, infarctions, necrosis, seizures and delirium are among the potential consequences of prolonged, severe fevers. The receptor environment at the hypothalamus maintains limitations on high fevers. In the rare instances in which the hypothalamus itself malfunctions, the result is typically low body temperature, not elevated body temperature. What is the first thing that happens when body temperature increases above normal body temp?The thermostat in the hypothalamus activates cooling mechanisms; The first thing that happens when body temperature increases above its normal range is that the thermostat in the hypothalamus activates cooling mechanisms.
What happens to your body when your body temperature increases?When temperatures rise, the body reacts by increasing blood flow to the skin's surface, taking the heat from within the body to the surface. This means sweat. As the sweat evaporates, the body cools down.
What happens when the body temperature rises up significantly beyond the normal temperature?Hyperthermia, also known simply as overheating, is a condition in which an individual's body temperature is elevated beyond normal due to failed thermoregulation. The person's body produces or absorbs more heat than it dissipates.
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