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Medical Variable times of flu

  1. Apr 11, 2010 #1


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    How could it be possible that colds are more intense during certain times of the day? For example, right now I feel terrible in the morning, but I feel nearly fine during the day.
    This does leave me in an awkward predicament when I tell my parents I'm too sick for school, but then later on in the day I seem fine, only to be sick again the next morning.
  2. jcsd
  3. Apr 11, 2010 #2
    It would be more accurate to say that symptoms of illness tend (ESPECIALLY cold-flu) to intensify during that period when we would normally be tired. The reason... is that you're tired! Sleep plays a (not fully understood) deep role in the efficacy of our immune response, so when you're getting ready for bed.

    It's also the case that people are less alert during certain period (3AM being notable in military history), but it's not JUST perception; if you have a fever, generally it will be higher at night. In the morning, your body temp is still usually depressed from sleep, but,

    1.) You're waking up sick. Never underestimate the psychosomatic roel of illness, or percetion of symptoms.

    2.) Resources that would otherwise have been used to repair damage incurred during the day, is partially re-routed to fuel your immune response.

    On a less exciting note, being supine (on your back) often results in post-nasal drip, which can make your throat quite sore, for a while...
    During the day, you are likely hydrating, and taking some form of medication (to ease symptoms). Then, there is just the fact that infections follow a GENERALLY similar pattern, but some wax and wane depending on how healthy you were upon becoming ill.

    There are reasons related to metabolism as well... you produce more urine during the day, etc...

    In short, when you're up, around, and awake... your body is working to minimize symtpoms, as are you. When not... not, and some of the aspects of sleep (hormones relating to, again, production of urine, and digestion, etc...) are not conducive to FEELING better. This should be distinguished from a lack of improvement, or a true remitting-relapsing fever.
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