The first thing any British child will ever taste, after milk, will almost certainly be Calpol. The NHS advises parents to give their babies liquid paracetamol after infant vaccinations, which begin at eight weeks old. According to the UK’s medicines regulator, 84% of babies will have Calpol by the time they reach the recommended age of weaning at six months.

Calpol is only one brand of liquid paracetamol – but the sweet, viscous, strawberry-flavoured syrup in the purple box is as much a part of childcare as nappies, wipes, dummies and bottles. Babies learn to recognise that syringe well before they know how to use a spoon, and they anticipate it: their sticky fingers reach to put it further into their mouths.

The NHS webpage explaining how to give any medicine to children uses an image of a baby sucking from a graduated syringe with a familiar purple plunger. More than five tonnes of Calpol is sold every day – and more than 12 million units each year. Other brands cost half the price, but Calpol has 70% of the market for children’s pain-relief medicine, which is three times the share of its nearest competitor and 50 times more than the next most popular brand of paracetamol. For British parents, Calpol is overwhelmingly the drug of choice.

This drug is found in found in bedrooms, bathrooms, nurseries and creches. Kitchen drawers across the country are littered with used Calpol syringes. There are more than 12,000 search results for Calpol on the talkboards of the British parenting website Mumsnet. But the more Calpol has become synonymous with parenting, the more its ubiquity has begun to worry us.

Over the past decade or so there has been a succession of panics over Calpol. Could it be behind the explosion in childhood asthma? Could its signature colourings and flavourings be the mysterious cause of the epidemic of ADHD? Worries over Calpol’s purported sedative properties have filled the pages of countless parenting forums.

Last year, a BBC documentary about overmedicated children set off another flurry of panic. After reporting that children swallow three times as many drugs as they did 40 years ago, the film-makers interviewed a family GP whose brief remarks filled the pages of tabloids and the sofas of daytime TV for the better part of a week. “We have children now who are almost addicted to paracetamol, to Calpol,” the GP said. “Some people describe it as the heroin of childhood.”

Like all paracetamol products, Calpol eases pain and lowers fever, but we give it to babies who are too young to tell us what is wrong with them in the hope it will soothe them. For many, Calpol is a panacea, a cure for baby-crying, a reliable way to settle your child and send them off to sleep. At a time when we are being forced to recognise the dangers of so many everyday items, from plastics to bacon to toilet seats, we fear that the ubiquitous solution in the brown glass bottle must have some kind of dark side.

In short, Calpol makes us feel guilty. It has become a soft target for an anxiety exploited by scaremongers and conspiracy theorists. But British parents cannot live without it.

The medicine of British childhood is actually produced in a vast factory in a suburb of Orléans. Calpol is now owned by an American company, Johnson & Johnson, who have outsourced manufacturing to a French company called Famar. In their marketing, Johnson & Johnson like to remind us of how Calpol has been a go-to solution for generations of British parents, but the company only acquired the brand in 2006, and don’t have much information about its history. They have never given an interview about Calpol before: pharmaceutical companies don’t really do press junkets.

After several months of emails about Calpol, they invited me to their British headquarters in Maidenhead, where the receptionists wear the company colours – white shirts with red neckerchiefs – as if they were stewardesses on a Johnson & Johnson airline.

Johnson & Johnson call the Calpol range of medicines The Calpol Family. “From stuffy noses and sore throats to aches and pains, fevers and teething,” the brand’s website promises, “we’ve carefully developed a family of effective medicines to help you take great care of your little one” – as if describing a crack team of solutions to almost any health problem the average child will encounter.

“It’s a brand that we’re really proud of,” Purvi Farahi, the head of marketing for Northern Europe told me. She sat with Gill Nelson, the medical director for Northern Europe, in a white boardroom with red chairs; on the other side of the table was a PR consultant who was taking notes and recording every word of our conversation. “For over 50 years, it’s a brand that parents, grandparents and caregivers have grown up with. At the heart of it, I think it’s really about trust.”

Trust in the Calpol brand is the reason people choose it over cheaper alternatives: parents are buying “the experience of the overall product”, Nelson told me. “When you’ve got a poorly child and you really want to make them feel better, it’s not really a time when you want to start browsing the shelves.”

Dr Andrew Green, a GP in Yorkshire and the British Medical Association’s GP committee clinical and prescribing lead, took a dimmer view of our collective loyalty to the Calpol brand: “In our society we have the idea that expensive things are best,” he told me after my trip to Maidenhead. “Buying the expensive one that’s the familiar one with the nice bottle and the advertising means parents are doing the best for their child.”

Calpol’s formula is as central to its success as its familiarity. “The active ingredient is paracetamol, but the other ingredients – what we call the excipients of the product, all the other bits and pieces that are put in to make sure it doesn’t go off in the bottle, has the right consistency, can be extruded into a syringe for dosing, tastes acceptable and looks acceptable to children – all those are unique to Calpol,” Nelson explained, deftly avoiding the words “colouring”, “preservatives”, “flavourings” and “sweeteners”. Calpol has 2.2g of sucrose per 5ml, which is more than four times as much sugar as there is in an equivalent amount of Coca-Cola. No wonder children can’t get enough of it.

Prof Mahendra Patel, a pharmacist and board member of the Royal Pharmaceutical Society, told me that Calpol’s tasty formula has made all medicines more palatable for children. “Calpol educates that baby to say, actually, I will have that medicine, I won’t spit it out. In terms of any medication the child takes thereafter, the seed has been sown that medicines aren’t bad.”

Illustration: Ryan Chapman

You don’t have to go to a pharmacy to buy Calpol: it’s sold in petrol stations, newsagents, corner shops and supermarkets. If you can get a pint of milk, you can probably buy a bottle of Calpol alongside it. “Availability is really important, particularly for a medicine of this type where it often is a purchase that you’re making in a really stressful situation,” Nelson said. This doesn’t quite ring true to me: I have never waited until my children were ill before buying some. Indeed, the NHS website says it’s “a good idea” to keep children’s paracetamol always stored at home.

Patel has witnessed the power of the brand first-hand. He began his career working in areas that were densely populated with recent migrants from Pakistan, India and Bangladesh. “Families with small children were coming through the pharmacy and they didn’t speak the language, but because Calpol was Calpol it didn’t need any translation: they knew it was the solution to many of their children’s minor problems.”

The nurses who run immunisation clinics routinely tell parents to give their babies paracetamol to avoid adverse reactions, particularly after the meningitis B vaccination, which has a more powerful inflammatory response, was recommended for all infants in 2015. When my baby was immunised last year, the nurse explicitly told me to “go and buy some Calpol” to give her afterwards. This means many first-time parents’ first encounter with children’s medicine is a healthcare professional telling them to use it before their child is ill, setting up a relationship whereby we give it before we’re sure it’s needed.

Under the watchful eye of the UK’s Medicines and Healthcare products Regulatory Agency (MHRA), Calpol has managed to produce marketing messages that promise what every parent wants to hear. One recent advertising slogan is “Lets Kids be Kids”, and TV adverts emphasise how Calpol can “help them get back to normal”. A Calpol booklet offering an immunisation guide for parents depicts a blissed-out baby asleep with her arms outstretched and a smile on her face. Sick children don’t have a role to play in Calpol’s marketing strategy: the messages emphasise the emotional rather than medical reasons for giving the medicine. By focusing on the positives, they give the impression that Calpol can cure your child’s discomfort, no matter what the reason for it might be.

When I put this to Farahi, she told me this was intentional. “The strategy for us is always to show the end benefit that parents are looking for,” she said. But their marketing strategy is about more than being back to normal: it’s about portraying children who have had Calpol as being happy, or asleep, or both.

Johnson & Johnson hold competitions every few years to find the new face of Calpol – a coveted role in marketing and packaging, on par with being the Pears or Gerber baby. More than 24,000 parents entered their children into a “Be a Calpol Star” competition on the brand’s Facebook page in 2011. When two year-old Millie Foster became “the Calpol Kid” in 2006, which meant her face appearing on the box, her mother, Georgina, was ecstatic. “Everyone will have her in their cupboards now. Her granny and grandpa are very proud,” Georgina told her local paper, the Surrey Comet, but added that Millie actually “doesn’t like her photo being taken at all”.

Nelson said the main task for their marketing was raising awareness. “Something like 41% of babies are born to first-time parents. With every birth, there’s a whole new raft of potential customers arriving on the scene.”

In the 18th and 19th centuries, mothers rubbed paregoric – a waxy tincture containing opium – into their babies’ gums to soothe teething pain. As late as the mid-20th century, it was common to do the same with whisky or brandy, and “gripe water” containing alcohol, sugar, dill extract and baking soda was given routinely for colic. In the 1950s Gould’s gripe water was advertised with strapline “No more fuss from baby”.

Even though paracetamol is the most common medicine in paediatrics, no one is entirely sure how it works. We know it inhibits an enzyme involved in producing prostaglandins, making the body less aware of pain, but the mechanism by which it acts on the brain to reduce fever is less understood. We know the inputs and the outputs, but it’s a black box.

Paracetamol was discovered after a mistake at the University of Strasburg in the 1880s. Professor Adolf Kussmaul was experimenting with naphthalene, the main ingredient of mothballs, as a possible cure for intestinal parasites. His patients were accidentally given acetanilide instead, and while it wasn’t much good for worms, it dramatically lowered fever. Acetanilide was cheap and effective, but it also deactivated some of the haemoglobin in red blood cells, with potentially lethal results. Paracetamol, a derivate of acetanilide, was first used in clinical trials by the German pharmacologist Joseph von Mering in 1893, but fears lingered that it might still be dangerous, and it was only after a series of studies in the 1940s showed paracetamol to have no effect on haemoglobin that it began to be widely sold.

Calpol was launched in 1959 by Calmic Limited, based in Crewe. (It’s likely the Calpol brand name comes from the contraction of “Calmic” and “paracetamol”.) At the time, paracetamol was being given to children in solution and tasted extremely bitter; Calmic was the first to suspend it in a sweet, flavoured syrup. When Calmic was bought by Wellcome in 1966, aspirin was going out of fashion as a painkiller because it had been linked to gastro-intestinal bleeding. Wellcome marketed Calpol as “Better and safer than aspirin because it is a non-irritant”. It was prescription-only at this point, but prescription medicines could be legally advertised until 1978. One of the first print adverts for Calpol reads: “Calpol Suspension is a flavoured liquid – very pleasant to take from a spoon. As you know, this can be a great help when your child is ill or upset.” It sold parents calmness, just as it does today.

Calpol’s advertising slogans of the mid-70s (“Simple answers to everyday babycare problems”, “Gentle and comforting, pleasant tasting too”) positioned it as more than a medicine: a comfort for your child, a solution for you. One late-70s slogan, “Pleasant for baby, peaceful for you”, is the closest the brand has ever come to explicitly claiming Calpol has the ability to make crying babies shut up. The sentiment was echoed in an animated television advert in the 1980s featuring a grumpy, grizzly baby. “There are times when every baby is just crying out for Calpol infant suspension,” the mellow voiceover says, as the child’s frazzled parents stand over his cot in their pyjamas pouring it into a spoon. “It makes everyone feel better.”

By the 1980s, Calpol could be bought from pharmacies without a prescription, and it became one of Wellcome’s best-selling products in the UK, with more than a million bottles sold over the counter in 1983. Babies began to be given Calpol routinely after vaccinations. Calpol was now such a normal part of British parenting that it was being marketed as something you pack in your suitcase when you go abroad. “When the family go on holiday don’t take the risk of aches and pains,” read a 1980s print advert, next to a cartoon of a feverish child on a beach. Discomfort had become something a “concerned parent” shouldn’t want to risk.

When British parents began to worry about sugar and additives, sugar-free Calpol was launched in 1988, and a colour-free version arrived a few years later. When we became obsessed with 24-hour convenience in the late 1990s, Calpol switched from being a pharmacy-only medicine to one sold in any store. Since acquiring the brand in 2006, Johnson & Johnson have expanded the Calpol “family”, launching a version that was both sugar-free and colour-free in 2011, and adding a saline nasal spray and a plug-in vapouriser that releases chamomile and lavender essential oils supposed to assist sleep; after all, this is a brand that parents have long associated with sleeping children.

Illustration: Ryan Chapman

The link between Calpol and sleep has been discussed in countless Mumsnet threads since the site launched in 2000. In one entitled “Dosed on Calpol – feeling guilty”, a mother tortures herself for giving her six-month-old a dose purely to make him drop off. Other parents weigh in to reassure her. “Calpol wont send him to sleep. he was obviously in discomfort with pain/temp somewhere, and the calpol worked,” one says. “I just assumed that it was slightly sedative,” the mother replies. “I guess you can’t use it forever though so where do you draw the line?”

In 2007 Johnson & Johnson introduced a new product: Calpol Night, for children aged two years and up, with added antihistamine, to explicitly aid sleep. But in 2009 the MHRA ruled that 36 different medicines, including Calpol Night, should no longer be given to children under six: research had shown them to be of limited use in younger children, and linked them to side effects such as disturbed sleep and hallucinations. Even though Johnson & Johnson could have continued to market it for older children, Calpol Night was quietly withdrawn in 2010.

Doing the very best for your children today means not ever allowing them to suffer. But the generation of parents who are increasingly unwilling to leave their children to cry at night are the same parents who are prepared to dose them up with a nightcap of paracetamol and antihistamines to make them sleep.

Prescriptions for ADHD medication have doubled in the past decade, and prescriptions of adult sleep medication given to children have increased tenfold over the same period. But because Calpol is such a ubiquitous part of everyday parenting, every anxiety over children’s medicines seems to be projected on to Calpol.

The fame of Calpol is so great that it was even dragged into the investigation of Madeleine McCann’s disappearance in 2007. The Portuguese police were under pressure to come up with new leads, and their attention briefly turned to whether Madeleine’s parents, who were doctors, had accidentally killed her while trying to sedate her. Leaks from the investigation appeared in a Portuguese newspaper, claiming an oral dosing syringe had been found in their holiday apartment. The McCanns readily admitted that they occasionally gave their children Calpol, but strongly denied administering anything stronger. There was no basis whatsoever for the theory, which has been completely discredited. But still the Calpol detail was seized on by conspiracy theorists and tabloids alike: the combination of the nation’s most famous missing child and our best-loved children’s medicine was too sensational to resist, even though the most basic research would show that Calpol contains no sedative ingredients at all.

Many of the subsequent panics have been similarly fact-free. “Babies given Calpol just once a month ‘are five times as likely to develop asthma’” declared a headline in the Daily Mail in 2013. The Mail was only one of many newspapers to dramatically misreport the results of a study of 20,000 Spanish children: Calpol isn’t even sold in Spain; the study measured paracetamol use alongside asthma symptoms, but failed to find a causal link. The NHS issued a response debunking the reports, but the story still gets repeated in newspapers today.

When a campaign group called later that year for food colourings linked to hyperactivity to be removed from children’s medicines – all children’s medicines – the press brought up Calpol’s signature purple hue: the headline in the Times read “Hyperactivity link to additives in Calpol”. Johnson & Johnson said in an email that they use colourants – including “Sunset Yellow” and “Carmoisine”, which were linked to hyperactivity, though only with much higher doses than are found in Calpol – “to make the medicine look more visually appealing to poorly children who otherwise might refuse the dose”, adding that “the majority of children will experience no ill effects from consuming the tiny amounts of colourants in Calpol”. Of course, you could just buy the colour-free version – but the original purple formula remains the best-seller.

But it was the GP’s offhand remark about Calpol as the “heroin of childhood” that caused the greatest flurry in the British tabloids. In 2018, a BBC series called The Doctor Who Gave Up Drugs looked into whether we are overmedicating our children. The presenter, Dr Chris Van Tulleken, took his baby daughter to be vaccinated and then interviewed his family GP. “We have children now who are almost addicted to paracetamol, to Calpol. I don’t think they are addicted to the drug itself, but they are addicted to the process,” the GP said. “Some people describe it as the heroin of childhood.”

The image of the Calpol-junkie baby was too powerful to leave room for nuance. Parents left angry messages on Calpol’s Facebook page after the broadcast. “My children are teenagers now but I’ve learned things tonight that I never questioned before – I feel like I’ve been misinformed during their formative years,” said one. “Anybody working for this organisation needs to have more integrity,” said another, “speaking as a concerned mum.”

But Chris Steele, doctor-in-residence on ITV’s This Morning programme, issued a robust defence of the brand on air. “Every parent will be thankful for the paracetamol Calpol syrup,” he said. “It’s not addictive. However, parents, I think, are psychologically dependent on Calpol, because when their children are ill they do go for the Calpol. Well, that’s all right, so long as you follow the recommended dosage. It’s totally safe.”

Calpol is very safe if given according to the instructions on the pack. (The only real danger is an accidental overdose, and these are very rare.) But our dependence on it makes us uneasy, which is why the scare stories refuse to die. As both scaremongers and marketing departments know, parental concern is a lucrative seam to mine.

Johnson & Johnson reject the idea that parents are giving their children too much Calpol. “We don’t have any evidence that it’s overused,” Nelson said, and Farahi cited independent research data to back this up: “On average, households purchase 1.95, so say around two bottles a year of Calpol,” she told me. “Usually there’s about 1.75 kids in a family, roughly two.” One bottle per child per year doesn’t sound like much, but an average figure takes in families of children of all ages, and, as any parent knows, Calpol is used more frequently with babies than with older kids.

As much as paracetamol is a black box, so are babies: they are non-verbal, their internal states are opaque, and we have to work out what’s wrong with them when they are upset. “There seems to be a default action to give it to a distressed child, whether or not that child has a temperature or fever,” Dr Andrew Green told me. This happens at the other end of the age spectrum, he said. “Where you have an adult with dementia who is distressed, then it’s a quite reasonable therapeutic intervention to try some regular low-risk medication like paracetamol, because sometimes people can’t communicate pain. I wouldn’t in any way criticise parents for giving it to distressed children. There are rational reasons for doing it.”

Calpol’s packaging says it is for the relief of pain and fever, but we give it for distress, and the brand has always encouraged this in its marketing. There are many reasons why a drug containing no known sedatives might make a child calm and sleepy. The most obvious is that it alleviates the pain or physical discomfort from fever that was preventing them from sleeping. But it is likely Calpol’s power derives primarily from its ability to comfort parents.

“One of the things that determines the distress in the child is the distress in the parent. Children and babies are extremely good at picking up anxiety,” Green told me, describing how babies at immunisation clinics are always more upset by the injection when their parents are fretting. “It’s upsetting for parents to have an ill child, and natural for parents to want to help that ill child. Giving the child medicine is a way of helping. The act of giving the Calpol assumes far more importance than the mere giving of a medicine: it’s an expression of love, and it reduces tension. It’s almost a placebo effect by proxy: the child benefits from the parent believing that they’re doing good.”

We are dependent on Calpol – but it is parents, not kids, who are addicted. It is understandable that a medicine could come to take such a central role in family life. Parents are increasingly atomised, separated from wider networks of extended families and community that used to pass wisdom down. When there is a problem with our children, we are as likely to reach for Google as to ask a friend. Calpol has stepped into that void, producing booklet guides to immunisations, and online advice on teething, earache, colds, flu and many more common minor health problems. The Calpol website hosts several information videos featuring groups of mums sharing a pot of tea with a GP around a wooden kitchen island, comparing notes about how to recognise a fever, the flu or a new tooth. The site gets over more than a million hits a year.

But by turning to Calpol whenever our child is distressed, we contribute to an already rampant culture where problems are supposed to be solved by medication. “We can forget, in all stages of our lives, the non-drug interventions that are effective, the simple things that we can do,” Green said. “Every time a GP does an emergency or a turn-up-on-the-day type of surgery, we will get an embarrassed mum in with a child who is running around the room giggling. They will say, ‘I brought him here because he’s really ill with a temperature, but he’s got better.’ The reason they’ve got better is that they are in an environment that is interesting, and they’ve had a ride in the car or bus or pushchair and cooled off a little bit.”

Johnson & Johnson insist the wider Calpol range, with its nasal spray and vapour plug, offers non-drug alternatives for those who want them. But perhaps it would be more useful to look at this the other way round: it’s not so much that we believe the answer to our children’s discomfort is drugs, but that we don’t view Calpol as a drug. It has infiltrated our daily lives and most protected spaces. It is part of solving our babies’ problems in the same way as a dummy, a cuddle or a nappy change is. Many are as likely to reach for Calpol as they are to rock their babies when they are very upset.

Some of this is due to clever marketing, which, over decades, has established the brand as a “simple answer”, an “everyday” part of having kids. Some of this comes from its ubiquity – the fact that it can be bought at the same time as we buy our loaf of bread or fill the car up with petrol. Calpol has become the brand of medicine that we don’t regard as a drug, no matter what its manufacturers might print on the pack. That is the secret of its success.

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