Can I unilaterally change the dose and duration of ds' antibiotics?

[Fauve]

This is a bit complicated, so bear with me
Ds has had stomach cramps about every ten days for the last 18 months, and has tested negative for coeliac disease and lactose intolerance. The consultant wanted next to rule out giardia, so ds was prescribed Flagyl - metronidazole - at a dosage of two 200mg tablets three times a day for 7 days. Tomorrow is the last day.
However, on Tuesday he is due to do a four-day sailing course on a lake - part of a series of courses to allow him to join a club in the summer. I've only just twigged that IF he ever had giardia, it could only have been from sailing on that lake; and therefore that if he does the course, he might conceivably reinfect himself with giardia. That would negate the whole point of him taking a week's worth of antibiotics, since they were to act as diagnosis as well as cure - ie if he never had the stomach cramps again, then giardia must have been the cause of them.
If only the course of antibiotics lasted until Friday, all would be well and there would be no chance of reinfection. On that basis, I'm tempted to prolong the course of antibiotics until Wednesday by reducing the dose he takes from Monday morning. There would be enough for him to take one 200mg tablet three times a day until Wednesday evening; and then the pills stay in the system for 48 hours, so in theory he would be covered until Friday. He would have had six days at the full, strong dose and three days at the weaker dose. The Flagyl website recommends that lower dose for five days as the minimum dose for adults and children over 12 - ds is 13.
Alternatively, I could let him do only two days of the sailing course and no more; or none of it.
Prolonging the pills seems to me to be the common sense thing to do - or am I wrong? And just to clarify - there's no substantial reason to think he has ever had giardia: only the stomach cramps, which may be due to another food intolerance.

No, you shouldn't change the dose and duration without consulting a GP. I know it's a holiday weekend so you won't get to see your own, but phone the local out of hours service, explain the situation to them and ask what to do. They may tell you to go ahead or offer an alternative.

Of course changing the dose yourself may have no bad effects, but you can't possibly know beforehand, so I'd phone.

I think consulting a health professional is the only sensible thing to do. They may give your plan the ok, or they may prescribe more tablets so that he can extend the course until Friday? I am not sure what the effect would be to reduce the daily dose - it may mean the antibiotics are not effective? Otherwise why would they prescribe 6 per day?

I would not alter the dosage as you will then make the antibiotic ineffective if he has Giardia (why did GP not send stool sample? That would have confirmed diagnosis?)

Also, not using antibiotics at the correct dosage can cause organisms to become resistant to treatment. I know the websire says 200mg as minimum dose but usually dose of choice is 400mg.

I would call GP and have course extended at correct dose if need be, or at least discuss your plan with him.

Thanks - the consultant refused to send a stool sample, saying they weren't reliable. I rang NHS Direct, but the dr said the risk of him re-contracting giardia was small. However, for me, that's not really the point - it still invalidates him having taken the antibiotics to exclude giardia.

Damn, damn, damn. I could try and see our GP first thing on Tuesday - although after a bank hol, that might be tough. In any case, if he doesn't do the course I'll need a dr's certificate to get the money back.

Thanks for your comment re resistance, mears - that's what dh is afraid of.

I'm actually really upset about this, because the consultant refused to discuss giardia with us properly, just wrote out the prescription. If he'd been prepared to discuss it, I would've twigged the possibility of the lake being its source, and would've made sure ds was taking the pills while on the sports course. Now I have to mess up ds' hols for what might have been nothing all along. There may never have been any giardia in that lake, anyway, ever.

My little neice had giardia a number of years ago. She was on holiday here from Zambia and she had appalling diarrhoea. Does your son have anything other than stomach cramps? A stool sample was sent, the result of which came back after she had gone home. We had puiblic health inspectors at the door to follow her up!

Could your DS have stomach migraines at all? Has that been excluded? I don't think a course of antibiotics could give a positive diagnosis of giardia.

If there is giardia in the lake, that should not mean your DS shopuld have antibiotics when he goes sailing does it? Are there not simple precautions he should be taking if it is the case it is giardia?

\link{http://www.hpa.org.uk/cumbriaandlancashire/factsheets/GIARDIA.pdf\is this any use?/

here

this one is better

last one I promise

nothing intelligent/insightful to say. but sympathy anyway.

Thanks, boysontoast, what a sweet message! And thanks again, Mears. That last link is interesting - it says kids his age can take the Flagyl for up to 10 days, so maybe that's an option. I'm now thinking I'll have to queue up at the GP surgery first thing on Tuesday and try to see a doc, asking for one of two things, either:

• to get a certificate saying he can't do the sports course; or
• to get 3 days' more Flagyl, assuming that on Friday he'll be covered by the residual amount left in him.

I just hope they can see us in the morning on Tuesday.

It does look like he could've been tested by a stool test . As it is, we have always thought it's only an outside chance that he's ever had giardia. He doesn't have diarrhoea.

It could be stomach migraines, although he's not a nervous child. What's the diagnosis process and treatment for that, Mears? Funnily enough, my GP originally thought that a possibility, but we went down the coeliac investigation route instead. We deliberately fed him pizza and garlic bread today - usually his trigger foods - hoping that he'll get his usual symptoms and show that it's nothing to do with giardia. We won't know till tomorrow though!

Perhaps you wouldn't need to see him Fauve - If you could get to speak to him on the phone maybe he'd just issue a new script?

No, it wouldn't work - I'd only get to speak to a locum, and they are generally pretty useless. It's a weird and complicated situation, which I don't think will be taken seriously unless face to face. The NHS Direct doctor was more or less saying 'let him do the sports course, he's not likely to catch giardia' but that misses the point - that we really must exclude giardia at this crucial point in the proceedings. Ds is missing one school day in seven - secondary school - so it's no joke: we have to find out what's giving him so much pain. His school has even rung us to ask why he's off school so much!

Oh I see.

Hope you can get it sorted, it seems a shame to have been on the anti-b's and not be any further on.

And sympathy re school - dd is a dire attender due to ill health. I'm quite skilled at fending off the EWO.

Thanks, sorry to hear about your dd. I get incredibly stressed about ds' mystery illness, especially when he's in a lot of pain. I suppose it's the burden of motherhood I'm sure we'll get to the bottom of it eventually.

Not sure about diagnosing stomach migraine - my friend's DS had it and was presribed medication which helped. Worth finding out more i would say - homeopathic medicine can be really useful for migraie. Another friend's DS had traditional migraine which wasn't helped by traditional medicine. She saw homeopathic doctor who made a huge difference with her medication.

Well, this morning he has no cramps in spite of having eaten a lot of his usual trigger foods. Dh is out atm feeding him some more! If he continues to have no pain, then it looks increasingly likely to have been giardia, I guess.

Thanks for the stomach migraine info, Mears. We already see a homeopath regularly but have been waiting for test results (for coeliac, lactose intolerance and now giardia) before really tackling the issue homeopathically. However I have some remedies to help him get over the Flagyl.

I still plan to queue up for the GP tomorrow and just see what they say.

Well, we queued up at the surgery at 7.45 this morning and got an appointment at 8.30 hooray! And the Dr gave us a prescription for a further four days, so I feel relieved. He did say ds would have to be extremely unlucky to catch giardia locally, so I think the script was a concession to my neurosis, but hey that's the kind of mother I am

Interestingly, though, ds still has had no stomach cramps since starting the Flagyl. We're really hoping he never gets them again, and that it was all down to a dose of giardia. What a relief if it was all over now.

Thanks again, everybody, for helping me work out what to do. MN is such a help to me when I'm thinking of doing something daft - like deciding to dose my ds with antibiotics without consulting a doctor...Also it gives me courage to speak to the doctor sensibly once I get there

that's a bit of a result, fauve, welldone

Yay! Hope he enjoys his sailing Fauve and stays cramp-free

Thanks, everyone Still no stomach cramps

Glad you got it sorted