My 25-year-old daughter has had a bad viral infection. She's better now but seems really tired all the time. This has been going on for two weeks now, should I be worried?

Tiredness following a viral infection is not uncommon.

If your daughter has muscular pain or headaches then a painkiller such as aspirin or paracetamol will help, however, it seems that the best relief for post-viral fatigue is rest and not overdoing activities. Your daughter should also stick to a healthy diet and avoid stress and her symptoms should ease over time. It can take six or more weeks for her symptoms to improve.

If any additional symptoms appear or if she begins to feel less well rather than better, a trip to the GP for a repeat check up would be in order.

I'm in training for a charity run early next year. A couple of weeks ago I got very bad cramp in my leg and every time I go training it comes back, what should I do?

Muscles use salts and oxygen in a different way when they are working harder, such as during exercise. Most leg cramps come on suddenly and do not last very long.

Painkillers are unlikely to help because the cramp will probably have passed before the drugs take effect; however, if a severe leg cramp leaves your muscle feeling tender afterwards, you could take a painkiller such as paracetamol.

Make sure you drink plenty water before, during and after your running sessions.

Stretching exercises can also help to reduce how often you get leg cramps.

Try doing the exercises three times a day, including just before you go to bed. Straighten your leg, bend your ankle backwards, and try walking around on tiptoes for a few minutes.

Lean forward against a wall with your arms outstretched, about a metre from the wall.

Keep the soles of your feet flat on the floor for five seconds - repeat this exercise several times, for about five minutes.

If these exercises improve your cramps and reduce how often they occur, you may be able to do the exercises just once or twice a day. Warming and cooling down with stretches when exercising can also help.

WHAT is Addison’s disease?

Aalso known as primary adrenal insufficiency or hypoadrenalism, Addison's disease is a rare disorder of the adrenal glands.

The adrenal gland is damaged, and not enough cortisol and aldosterone are produced.

Early-stage symptoms of Addison’s disease are similar to other more common health conditions, such as depression or flu. You may experience fatigue, muscle weakness, low mood and loss of appetite.

Over time, these problems may become more severe and you may experience further symptoms, such as dizziness, fainting, cramps and exhaustion.

The condition is usually the result of a problem with the immune system, which causes it to attack the outer layer of the adrenal gland (the adrenal cortex), disrupting the production of steroid hormones aldosterone and cortisol. It's not clear why this happens, but it's responsible for 70-90% of cases in the UK.

Addison’s disease is treated with medication to replace the missing hormones. You'll need to take the medication for the rest of your life.

With treatment, symptoms of Addison's disease can largely be controlled. Most people with the condition live a normal lifespan and are able to live an active life, with few limitations.

However, many people with Addison's disease also find they must learn to manage bouts of fatigue and there may be associated health conditions, such as diabetes or an underactive thyroid.

An adrenal crisis is a medical emergency. If left untreated, it can be fatal. If you or someone you know has Addison’s disease and is experiencing severe symptoms, dial 999 for an ambulance.