Peak flow dropping but no other symptoms?

Wonder if someone can tell me if this is normal/what it means. Normally I can tell that my asthma's getting worse because of my symptoms which usually come with a fall in peak flow. I rely more on my symptoms rather than numbers as for me this seems more accurate/safe. I don't have an asthma action plan yet as I've only in the last month got my meds really well sorted and got back up to a good everyday peak flow.

However, I measure my peak flow every morning and evening and I've noticed it's been dropping a tiny bit over the last few days and today it dropped down by 60 from yesterday morning. It's still at an OK level and if it got worse I would get help (I have a GP appointment tomorrow anyway so can ask), but the odd thing is that although my peak flow has dropped, I don't have any of my asthma symptoms (unless I exercise) and feel that it's currently well controlled.

Is this normal? Can you get a drop in peak flow without other symptoms? What causes it?

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I take it you have had a peak flow near your best for a drop of 60 to still put you in the OK area. I,ve had the same with no symptoms in the past, if it keeps dropping for 3 or 4 days then I find that by this stage I will then start to notice something not quite right. I've always assumed that the drop is down to one of two things, 1st is that you have slight infection/inflamation in the lungs, but nothing that you can feel, or 2nd that the muscles have become tired due to exercise or all the puffing taking peak flow readings. Glad to hear that if things got worse that you'd get help, thats the important bit. Keep an eye on the PF readings, and it will be intersting to hear what the doc says.

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when i get a PF drop, if its a sudden one, its very usually followed by wheezing and coughing. If its more gradual, I know to be on my guard.

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Well my peak flow took another drop this morning, and even though these drops started from my best PF of 500 I would now be well into my yellow zone given the percentages on an asthma action plan and heading down. I saw my GP this morning who was a bit concerned but also confused (as I am) that I appear to be well and not have any symptoms. The only possible suggestion she could give was that I'm having an allergic reaction to one of my non-asthma medications (the one that's caused the mega itching, so I can see that it is a possibility) but I can't come off it straight away, so we're slowly cutting down the dose and seeing how I cope and considering alternatives and seeing if it helps and meanwhile keeping a very close eye on my peak flows with open access to the GPs this week if it gets much worse and I know when I need to get hospital attention (although I'm not sure what they would do if I was to turn up and say PF is 50% (or whatever) but I feel fine??).