Cough, low peak flow - help please?

[FlySwimmer]

Hi there, any advice would be appreciated.

I developed a very persistent cough in the autumn. Eventually went to GP, was prescribed antibiotics & steroids for a week. Didn’t really improve things. Chest X-ray and bloods clear. I’m now on an antacid medication, as there’s a suspicion it could be an acid reflux cough. That has helped, in that I’m coughing less, but it hasn’t got rid of it entirely: I’ll have coughing episodes in the evening, or first thing in the morning for example, though not every day.

I was also told to monitor my peak flow. Based on my age & height I should have a reading of c. 460, but I’m consistently around 350-380, ie lower than it should be. There’s a slightly variation of 10-30 between morning & evening. I don’t have asthma, at least not diagnosed.

I made an appointment for later this month in case things hadn’t cleared up, and debating about keeping it. I’m concerned about the peak flow as it’s worrying that it’s lower than it should be: I exercise quite a bit (swimming, gym). What could be done for this? Could I have developed asthma for example? Something else? Should I keep the appointment as it does appear the low peak flow is consistent, combined with the cough (though better than before). I guess I would appreciate to know what the next steps could be.

You might have later onset asthma. When you say it should be 460, have you ever consistently achieved that reading? Your capacity might normally be less. Do you check your SpO2 levels?

@LIZS the highest I’ve ever achieved on the peak flow was 410, and that was once. It’s generally between 350-380. I’ve tried several different ways of blowing into the reader, watched tutorials etc to make sure I’m doing it correctly, and it’s mostly stuck around those readings.

I don’t know what ‘normal’ would be as I’ve never done a peak flow before: I was asked to track it for a month in conjunction with this medication and the investigation of the cough.

I’ve remembered my fitness tracker can measure SpO2 so I’ve turned it on, to see what it’s like. I know it’s not completely accurate but might give an idea.