Last week, six types of cough medicine aimed at small children were removed from open shelves because of fears that parents could inadvertently administer dangerous overdoses to under-twos. This is alarming news to the many parents who view children's over-the-counter medicines as little more than strawberry-flavoured reassurance, assuming that it must be pretty foolproof.

"Parents often don't understand that an over-the-counter medicine can be harmful in too high a dose," Professor Steve Field, chairman of the Royal College of General Practitioners. The actual risks with children's cough medicines are not, however, enormous. Five British children under two years old have died since 1981 because of cough medicines - in each case their parents mistakenly gave them too much or used several different medicines with the same active ingredient, not realising that this constituted an overdose.

The Commission on Human Medicines (CHM) has only withdrawn six medicines - Asda Children's Chesty Cough Syrup, Boots Chesty Cough Syrup One Year Plus, Boots Sore Throat and Cough Linctus One Year Plus, Buttercup Infant Cough Syrup, CalCough Chesty and Bell's Children's Chesty Cough - from the shelves until they can be relabelled with warnings about not administering them to children under two (for older children they are still available via the pharmacist). Still, the concerns are real: in the US, where there have been similar cases of fatal overdoses, the Food and Drug Administration recently announced that cough and cold preparations should no longer be given to children under two years.

"Coughs and colds are generally self-limiting conditions, which will usually get better themselves within a few days," says Professor Rosalind Smyth, chairwoman of the CHM Paediatric Medicines Expert Advisory Group, which was behind the decision to remove the medicines from shelves. She recommends simpler treatments such as paracetamol and fluids.

So does Field. "There is absolutely no evidence that any cough medicines work on under-twos," he says. A single cough mixture may contain decongestants, cough suppressants, expectorants and antihistamines. "They can pack lots of different ingredients into one bottle," he says. "And since they don't work, why on earth would you give that to your child?" There is, he admits, a small amount of evidence that simple formulations of glycerol, honey and lemon could help soothe older children's coughs (though there is no evidence that this works for under-twos). You could, though, save your money by making honey and lemon drinks at home.

By far the most sensible approach, he says, is to "keep it very simple indeed. Keep your child cool, give them plenty to drink, use paracetamol or ibuprofen to help reduce temperature and ease pain." For blocked noses, steam can help "liquefy the snot".

It would be easy to think that someone would have to be either negligent, stupid or extraordinarily tired to overdose their child. Not necessarily, says Field. "The smaller the child, the more susceptible to dosages they will be because their bodies are so little." Even paracetamol - the active ingredient in drugs such as Calpol, "has potentially very harmful effects on the liver, which really can't tolerate much of it. This is why you should not go above the safe dosage for your child's age and weight."

This certainly does not chime with the image of these medicines. Advertising by the big brands appeals to raw parental emotions - love, fear, guilt. Give Calpol "when your little one needs more than just a kiss" coos the website of the UK's best-selling over-the-counter children's medication. "Keep those dreaded winter snuffles under wraps," urges Tixylix, another well-known brand. The underlying suggestion in these campaigns is that we are somehow negligent if we fail to administer drugs when our children are ill.

It is not unheard of for frazzled parents to administer Calpol as if it were a magical cure-all. "I regularly give my three-year-old Calpol when she is not sick at all," says Jenny, a mother of two children under six. "Faced with an overtired, screaming toddler at bedtime, who you know will calm down with a quick spoonful, it's almost impossible not to do it." The medicine, she believes, works as a placebo. "It calms her down straight away."

Sedating a child using cough mixture is another shockingly common parental trick. "I sometimes give my children cough medicine purely to get them to sleep," says Linda, a mother of three children aged two, five and six. "I'll do it on New Year's Eve, because I can't face them up at 5am. And I'll do it on long journeys. I also have no shame in giving them cough medicine for a few nights if they get into a pattern of night-time waking: they sleep through, and you break the pattern. This is infinitely preferable to a family that's so tired from night-time wake-ups that they scream at each other all day."

Field firmly diagrees. "Parents should only ever use medicines on children when they are really necessary," he says. "Sedatives are a waste of money since sick children are generally pretty groggy to begin with and you should only ever give paracetamol when your child is in pain or discomfort - has a fever, sore throat or earache." It is also important, he says, not to use more than one product at the same time, as they may contain the same active ingredient.

This generation is hardly the first to sedate wakeful children. Not long ago, a slug of whisky in the baby bottle was the method of choice. Yet perhaps this is the first generation for whom medication has become such an integral part of parenting. The proliferation of over-the-counter children's drugs seems to legitimise this. Calpol, for instance, now offers Calpol Night for babies aged over three months, which contains a sedative to "aid restful nights". Along with the medications, these brands set themselves up as authoritative parenting resources: the Tixylix website contains "Mum's Little Guide" to parenting. The Calpol website offers free "mini parenting guides".

We are, it seems, relying on drugs companies for reassurance as much as anything else. "New mums and dads can understandably get quite worried by normal childhood illnesses," says Field. "As GPs we spend a lot of time reassuring parents." Parents today are also less savvy than they were in the past. "People will give paracetamol to a feverish child, then wrap them up warm because they are saying they feel cold," he says. "In fact, they should do the opposite. The evidence base for treating a fever still shows that cooling a child down by taking off clothing and sponging them down and offering plenty of drinks is the most effective treatment of all." In other words, when it comes to children's coughs and colds, granny really did know best.

How to treat a cold

1 Cool a fever. Take off clothes, sponge with tepid water, off er plenty to drink (don't wrap a feverish, shivering child up warm).

2 Administer children's or baby ibuprofen or paracetamol in the correct dosage , and only if the child is feverish or in pain.

3 For children over two, glycerol, honey and lemon drinks may help soothe a cough (there is no proven benefit for under-twos and you should never give honey to babies under one).

4 Steam may help blocked noses: take your child into the bathroom with a hot bath running or into the kitchen with the kettle on. When babies are extremely blocked up, saline nasal drops could help.

5 Be patient: coughs and colds are a normal part of childhood, and usually clear up after a few days.