Elizabeth W. Covington, Auburn University

Imagine this: You’re at your doctor’s office with a sore throat. The nurse asks, “Any allergies?” And without hesitation you reply, “Penicillin.” It’s something you’ve said for years – maybe since childhood, maybe because a parent told you so. The nurse nods, makes a note and moves on.

But here’s the kicker: There’s a good chance you’re not actually allergic to penicillin. About 10% to 20% of Americans report that they have a penicillin allergy, yet fewer than 1% actually do.

I’m a clinical associate professor of pharmacy specializing in infectious disease. I study antibiotics and drug allergies, including ways to determine whether people have penicillin allergies.

I know from my research that incorrectly being labeled as allergic to penicillin can prevent you from getting the most appropriate, safest treatment for an infection. It can also put you at an increased risk of antimicrobial resistance, which is when an antibiotic no longer works against bacteria.

The good news? It’s gotten a lot easier in recent years to pin down the truth of the matter. More and more clinicians now recognize that many penicillin allergy labels are incorrect – and there are safe, simple ways to find out your actual allergy status.

A steadfast lifesaver

Penicillin, the first antibiotic drug, was discovered in 1928 when a physician named Alexander Fleming extracted it from a type of mold called penicillium. It became widely used to treat infections in the 1940s. Penicillin and closely related antibiotics such as amoxicillin and amoxicillin/clavulanate, which goes by the brand name Augmentin, are frequently prescribed to treat common infections such as ear infections, strep throat, urinary tract infections, pneumonia and dental infections.

Penicillin antibiotics are a class of narrow-spectrum antibiotics, which means they target specific types of bacteria. People who report having a penicillin allergy are more likely to receive broad-spectrum antibiotics. Broad-spectrum antibiotics kill many types of bacteria, including helpful ones, making it easier for resistant bacteria to survive and spread. This overuse speeds up the development of antibiotic resistance. Broad-spectrum antibiotics can also be less effective and are often costlier.

Why the mismatch?

People often get labeled as allergic to antibiotics as children when they have a reaction such as a rash after taking one. But skin rashes frequently occur alongside infections in childhood, with many viruses and infections actually causing rashes. If a child is taking an antibiotic at the time, they may be labeled as allergic even though the rash may have been caused by the illness itself.

Some side effects such as nausea, diarrhea or headaches can happen with antibiotics, but they don’t always mean you are allergic. These common reactions usually go away on their own or can be managed. A doctor or pharmacist can talk to you about ways to reduce these side effects.

People also often assume penicillin allergies run in families, but having a relative with an allergy doesn’t mean you’re allergic – it’s not hereditary.

Finally, about 80% of patients with a true penicillin allergy will lose the allergy after about 10 years. That means even if you used to be allergic to this antibiotic, you might not be anymore, depending on the timing of your reaction.

Why does it matter if I have a penicillin allergy?

Believing you’re allergic to penicillin when you’re not can negatively affect your health. For one thing, you are more likely to receive stronger, broad-spectrum antibiotics that aren’t always the best fit and can have more side effects. You may also be more likely to get an infection after surgery and to spend longer in the hospital when hospitalized for an infection. What’s more, your medical bills could end up higher due to using more expensive drugs.

Penicillin and its close cousins are often the best tools doctors have to treat many infections. If you’re not truly allergic, figuring that out can open the door to safer, more effective and more affordable treatment options.

How can I tell if I am really allergic to penicillin?

Start by talking to a health care professional such as a doctor or pharmacist. Allergy symptoms can range from a mild, self-limiting rash to severe facial swelling and trouble breathing. A health care professional may ask you several questions about your allergies, such as what happened, how soon after starting the antibiotic did the reaction occur, whether treatment was needed, and whether you’ve taken similar medications since then.

These questions can help distinguish between a true allergy and a nonallergic reaction. In many cases, this interview is enough to determine you aren’t allergic. But sometimes, further testing may be recommended.

One way to find out whether you’re really allergic to penicillin is through penicillin skin testing, which includes tiny skin pricks and small injections under the skin. These tests use components related to penicillin to safely check for a true allergy. If skin testing doesn’t cause a reaction, the next step is usually to take a small dose of amoxicillin while being monitored at your doctor’s office, just to be sure it’s safe.

A study published in 2023 showed that in many cases, skipping the skin test and going straight to the small test dose can also be a safe way to check for a true allergy. In this method, patients take a low dose of amoxicillin and are observed for about 30 minutes to see whether any reaction occurs.

With the right questions, testing and expertise, many people can safely reclaim penicillin as an option for treating common infections.

Elizabeth W. Covington, Associate Clinical Professor of Pharmacy, Auburn University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Stephanie N. Del Tufo, University of Delaware

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to CuriousKidsUS@theconversation.com.

“Do we need to read, or can we just get everything through audio, like podcasts and audiobooks?” – Sebastian L., 15, Skanderborg, Denmark

Let’s start with a thought experiment: Close your eyes and imagine what the future might look like in a few hundred years.

Are people intergalactic travelers zooming between galaxies? Maybe we live on spaceships, underwater worlds or planets with purple skies.

Now, picture your bedroom as a teenager of the future. There’s probably a glowing screen on the wall. And when you look out the window, maybe you see Saturn’s rings, Neptune’s blue glow or the wonders of the ocean floor.

Now ask yourself: Is there a book in the room?

Open your eyes. Chances are, there’s a book nearby. Maybe it’s on your nightstand or shoved under your bed. Some people have only one; others have many.

You’ll still find books today, even in a world filled with podcasts. Why is that? If we can listen to almost anything, why does reading still matter?

As a language scientist, I study how biological factors and social experiences shape language. My work explores how the brain processes spoken and written language, using tools like MRI and EEG.

Whether reading a book or listening to a recording, the goal is the same: understanding. But these activities aren’t exactly alike. Each supports comprehension in different ways. Listening doesn’t provide all the benefits of reading, and reading doesn’t offer everything listening does. Both are important, but they are not interchangeable.

Different brain processes

Your brain uses some of the same language and cognitive systems for both reading and listening, but it also performs different functions depending on how you’re taking in the information.

When you read, your brain is working hard behind the scenes. It recognizes the shapes of letters, matches them to speech sounds, connects those sounds to meaning, then links those meanings across words, sentences and even whole books. The text uses visual structure such as punctuation marks, paragraph breaks or bolded words to guide understanding. You can go at your own speed.

Listening, on the other hand, requires your brain to work at the pace of the speaker. Because spoken language is fleeting, listeners must rely on cognitive processes, including memory to hold onto what they just heard.

Speech is also a continuous stream, not neatly separated words. When someone speaks, the sounds blend together in a process called coarticulation. This requires the listener’s brain to quickly identify word boundaries and connect sounds to meanings. Beyond identifying the words themselves, the listener’s brain must also pay attention to tone, speaker identity and context to understand the speaker’s meaning.

‘Easier’ is relative – and contextual

Many people assume that listening is easier than reading, but this is not usually the case. Research shows that listening can be harder than reading, especially when the material is complex or unfamiliar.

Listening and reading comprehension are more similar for simple narratives, like fictional stories, than for nonfiction books or essays that explain facts, ideas or how things work. My research shows that genre affects how you read. In fact, different kinds of texts rely on specialized brain networks. Fictional stories engage regions of the brain involved in social understanding and storytelling. Nonfiction texts, on the other hand, rely on a brain network that helps with strategic thinking and goal-directed attention.

Reading difficult material tends to be easier than listening from a practical standpoint, as well. Reading lets you move around within the text easily, rereading particular sections if you’re struggling to understand, or underlining important points to revisit later. A listener who is having trouble following a particular point must pause and rewind, which is less precise than scanning a page and can interrupt the flow of listening, impeding understanding.

Even so, for some people, like those with developmental dyslexia, listening may be easier. Individuals with developmental dyslexia often struggle to apply their knowledge of written language to correctly pronounce written words, a process known as decoding. Listening allows the brain to extract meaning without the difficult process of decoding.

Engaging with the material

One last thing to consider is engagement. In this context, engagement refers to being mentally present, actively focusing, processing information and connecting ideas to what you already know.

People often listen while doing other things, like exercising, cooking or browsing the internet – activities that would be hard to do while reading. When researchers asked college students to either read or listen to a podcast on their own time, students who read the material performed significantly better on a quiz than those who listened. Many of the students who listened reported multitasking, such as clicking around on their computers while the podcast played. This is particularly important, as paying attention appears to be more important for listening comprehension than reading comprehension.

So, yes, reading still matters, even when listening is an option. Each activity offers something different, and they are not interchangeable.

The best way to learn is not by treating books and audio recordings as the same, but by knowing how each works and using both to better understand the world.

Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.

Stephanie N. Del Tufo, Assistant Professor of Education & Human Development, University of Delaware

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Leslie Root, University of Colorado Boulder; Karen Benjamin Guzzo, University of North Carolina at Chapel Hill, and Shelley Clark, McGill University

Pronatalism – the belief that low birth rates are a problem that must be reversed – is having a moment in the U.S.

As birth rates decline in the U.S. and throughout the world, voices from Silicon Valley to the White House are raising concerns about what they say could be the calamitous effects of steep population decline on the economy. The Trump administration has said it is seeking ideas on how to encourage Americans to have more children as the U.S. experiences its lowest total fertility rate in history, down about 25% since 2007.

As demographers who study fertility, family behaviors and childbearing intentions, we can say with certainty that population decline is not imminent, inevitable or necessarily catastrophic.

The population collapse narrative hinges on three key misunderstandings. First, it misrepresents what standard fertility measures tell us about childbearing and makes unrealistic assumptions that fertility rates will follow predictable patterns far into the future. Second, it overstates the impact of low birth rates on future population growth and size. Third, it ignores the role of economic policies and labor market shifts in assessing the impacts of low birth rates.

Fertility fluctuations

Demographers generally gauge births in a population with a measure called the total fertility rate. The total fertility rate for a given year is an estimate of the average number of children that women would have in their lifetime if they experienced current birth rates throughout their childbearing years.

Fertility rates are not fixed – in fact, they have changed considerably over the past century. In the U.S., the total fertility rate rose from about 2 births per woman in the 1930s to a high of 3.7 births per woman around 1960. The rate then dipped below 2 births per woman in the late 1970s and 1980s before returning to 2 births in the 1990s and early 2000s.

Since the Great Recession that lasted from late 2007 until mid-2009, the U.S. total fertility rate has declined almost every year, with the exception of very small post-COVID-19 pandemic increases in 2021 and 2022. In 2024, it hit a record low, falling to 1.6. This drop is primarily driven by declines in births to people in their teens and early 20s – births that are often unintended.

But while the total fertility rate offers a snapshot of the fertility landscape, it is not a perfect indicator of how many children a woman will eventually have if fertility patterns are in flux – for example, if people are delaying having children.

Picture a 20-year-old woman today, in 2025. The total fertility rate assumes she will have the same birth rate as today’s 40-year-olds when she reaches 40. That’s not likely to be the case, because birth rates 20 years from now for 40-year-olds will almost certainly be higher than they are today, as more births occur at older ages and more people are able to overcome infertility through medically assisted reproduction.

A more nuanced picture of childbearing

These problems with the total fertility rate are why demographers also measure how many total births women have had by the end of their reproductive years. In contrast to the total fertility rate, the average number of children ever born to women ages 40 to 44 has remained fairly stable over time, hovering around two.

Americans continue to express favorable views toward childbearing. Ideal family size remains at two or more children, and 9 in 10 adults either have, or would like to have, children. However, many Americans are unable to reach their childbearing goals. This seems to be related to the high cost of raising children and growing uncertainty about the future.

In other words, it doesn’t seem to be the case that birth rates are low because people are uninterested in having children; rather, it’s because they don’t feel it’s feasible for them to become parents or to have as many children as they would like.

The challenge of predicting future population size

Standard demographic projections do not support the idea that population size is set to shrink dramatically.

One billion people lived on Earth 250 years ago. Today there are over 8 billion, and by 2100 the United Nations predicts there will be over 10 billion. That’s 2 billion more, not fewer, people in the foreseeable future. Admittedly, that projection is plus or minus 4 billion. But this range highlights another key point: Population projections get more uncertain the further into the future they extend.

Predicting the population level five years from now is far more reliable than 50 years from now – and beyond 100 years, forget about it. Most population scientists avoid making such long-term projections, for the simple reason that they are usually wrong. That’s because fertility and mortality rates change over time in unpredictable ways.

The U.S. population size is also not declining. Currently, despite fertility below the replacement level of 2.1 children per woman, there are still more births than deaths. The U.S. population is expected to grow by 22.6 million by 2050 and by 27.5 million by 2100, with immigration playing an important role.

Will low fertility cause an economic crisis?

A common rationale for concern about low fertility is that it leads to a host of economic and labor market problems. Specifically, pronatalists argue that there will be too few workers to sustain the economy and too many older people for those workers to support. However, that is not necessarily true – and even if it were, increasing birth rates wouldn’t fix the problem.

As fertility rates fall, the age structure of the population shifts. But a higher proportion of older adults does not necessarily mean the proportion of workers to nonworkers falls.

For one thing, the proportion of children under age 18 in the population also declines, so the number of working-age adults – usually defined as ages 18 to 64 – often changes relatively little. And as older adults stay healthier and more active, a growing number of them are contributing to the economy. Labor force participation among Americans ages 65 to 74 increased from 21.4% in 2003 to 26.9% in 2023 — and is expected to increase to 30.4% by 2033. Modest changes in the average age of retirement or in how Social Security is funded would further reduce strains on support programs for older adults.

What’s more, pronatalists’ core argument that a higher birth rate would increase the size of the labor force overlooks some short-term consequences. More babies means more dependents, at least until those children become old enough to enter the labor force. Children not only require expensive services such as education, but also reduce labor force participation, particularly for women. As fertility rates have fallen, women’s labor force participation rates have risen dramatically – from 34% in 1950 to 58% in 2024. Pronatalist policies that discourage women’s employment are at odds with concerns about a diminishing number of workers.

Research shows that economic policies and labor market conditions, not demographic age structures, play the most important role in determining economic growth in advanced economies. And with rapidly changing technologies like automation and artificial intelligence, it is unclear what demand there will be for workers in the future. Moreover, immigration is a powerful – and immediate – tool for addressing labor market needs and concerns over the proportion of workers.

Overall, there’s no evidence for Elon Musk’s assertion that “humanity is dying.” While the changes in population structure that accompany low birth rates are real, in our view the impact of these changes has been dramatically overstated. Strong investments in education and sensible economic policies can help countries successfully adapt to a new demographic reality.

Leslie Root, Assistant Professor of Research, Institute of Behavioral Science, University of Colorado Boulder; Karen Benjamin Guzzo, Professor of Sociology and Director of the Carolina Population Center, University of North Carolina at Chapel Hill, and Shelley Clark, Professor of Sociology, McGill University

This article is republished from The Conversation under a Creative Commons license. Read the original article.