When ‘post viral’ fatigue is something more sinister
Q PLEASE can you explain postviral fatigue? I would like to know the symptoms and the cause of this medical condition. Is there is any medication to treat it?
David Ford, West Molesey, Surrey. A
RECOVERING from a viral infection, as most people will know, rarely happens overnight — we’re all familiar with the way it can take a week or two to completely get over a cold, a month or two to recover from influenza, or many months (in some cases) to get back to normal after an illness such as glandular fever.
This kind of tiredness is part and parcel of the infection and is what I would call genuine post-viral fatigue.
However, post-viral fatigue is sometimes also used as a label where people experience fatigue for which no cause can be detected — that is, there has been no infection.
To my mind, this suggests the cause has been inadequately investigated — it’s misleading at best, and dangerous at worst, as this presumption means another serious cause of the fatigue may be overlooked.
In medical terms, fatigue describes a sense of weakness that makes it difficult to engage in normal activity.
It may also describe an inability to maintain normal activity for long — I call that lack of stamina.
Fatigue is described as ‘acute’ if it lasts for less than a month, and ‘chronic’ where the symptoms persist for more than six months.
The many causes of chronic fatigue include heart or lung conditions, hormonal or metabolic diseases, rheumatological disorders, neurological diseases, blood disorders such as anaemia and psychological conditions including depression.
Even if we look only at viral infections, there are a host that may lead to a fatigued state — influenza, pneumonia, HIV, viral hepatitis and cytomegalovirus (a virus that causes flu-like symptoms) are just a few.
A viral infection can also lead to low mood — fatigue may be an overriding symptom of this post-viral depression, but it’s not the only one: weight loss, sleep problems, irritability, tearfulness, poor memory and headaches are all possible signs.
It’s very important to recognise whether it is depression and not to sweep it under the carpet as ‘just’ post-viral tiredness.
With so many potential causes, there is no single pill that can provide the solution.
What the patient needs is supportive care from a doctor with the diligence to eliminate other causes.
Only once depression has also been excluded can they say it’s post-viral fatigue and give the patient a prognosis based upon their knowledge of the patient and their medical history.
Q HOW can I stop cramp? Is it caused by dehydration? If so, how much fluid ideally do I need to take daily? And is there any way that I can treat it at home without going to the doctor?
A. H. Clark, Waltham Cross, Herts. A
CRAMP is essentially a sudden, painful contraction of a muscle and people of all ages can experience it.
most commonly, it affects the leg muscles and 40 per cent of the over-50s will experience a cramp from time to time.
But the problem is also not uncommon in other age groups. Cramp is usually idiopathic (of no known cause), but can be more likely under certain conditions.
In one study, cramp was found to occur only at night in more than 70 per cent of those who experience it; both day and night in 20 per cent; and in the daytime alone in around 7 per cent.
And, just as we don’t know why it’s more common at night, it’s also unclear why cramp occurs twice as frequently in summer as in winter.
Cramp may be secondary to some medical complaints, too, including orthopaedic problems such as flat feet or hypermobility syndrome — where joints easily move beyond the normal range — because these conditions may put undue pressure on the muscles, making it more likely they will suddenly contract.
Cramp can also occur in neurological disorders such as parkinson’s disease and motor neurone disease, which are associated with irregular muscle contractions anyway.
metabolic disorders such as diabetes and having an underactive thyroid gland are also associated with muscle cramps, because these conditions can lead to changes in the way that muscle fibres function.
To answer your specific question, if you’re severely dehydrated — for instance, after extreme exercise or a gastric bug — then your body will be somewhat low in salt.
This can trigger cramps, as it makes the muscles more ‘irritable’ (miners used to add salt to their beer when they emerged from the mine at the end of a shift to stop cramps).
So, simply drinking more water isn’t the way to prevent cramp — nor would I advise people to start taking salt, because this could lead to issues such as hypertension.
But if none of these scenarios describes your experience, in terms of home treatment, taking vitamin B complex — a mixture of B vitamins — three times daily (30mg capsules), or vitamin E (a dose of 800 international units), at night have both shown benefit in small trials.
What we know is that this can be helpful in some people — but the reason why is not clear and it may even be a placebo effect.
If this fails, then you could try diphenhydramine (Benadryl) at night. This antihistamine, usually used for allergies, may be effective and is available as an over-thecounter pill.
There is a secondary side-effect, but there is no long-term risk from taking it.
In the past, a pill form of quinine was given, having been found to be effective in well-designed trials. This is no longer prescribed on account of the potential for serious, and even life-threatening, sideeffects occurring in up to 4 per cent of patients (such as abnormalities of heart rhythm).
One option is to try a small quantity (one 150ml can) of Indian tonic water each evening — this contains a small quantity of natural quinine, which may be sufficient to prevent your cramps.
It is easily available and safe at this dose — and it might just work.
WRITE TO DR SCURR
WRITE to Dr Scurr at Good Health, Scottish Daily Mail, 20 Waterloo Street, Glasgow G2 6DB or email drmartin@ dailymail.co.uk — include your contact details. Dr Scurr cannot enter into personal correspondence. Replies should be taken in a general context and always consult your own GP with any health worries.