Raina Telgemeier struggles to find the right words when she tries to describe the sinking, claustrophobic sensation of having a panic attack. “It’s kind of difficult to talk about,” she said.

But when she started drawing “Guts,” her new graphic memoir about the origins of her anxiety, she found she could convey the feeling through drawing.

“Comics are great because you don’t always have to talk with words,” she said. “You can talk with pictures and symbols, you can use color, you can use lines, you can use the medium to push ideas without having to fully explain them.”

In one arresting sequence of images in “Guts,” Telgemeier shows herself as a girl, struggling to talk about her fears in a therapy session and using a scale of 1 to 10 to rate her anxiety.

Telgemeier, 42, has built a fan base among young readers with her graphic novels and memoirs, including “Sisters,” a coming-of-age story about a fraught sibling relationship and an excruciating family road trip, and “Smile,” which chronicles her long and painful dental reconstruction following an accident that smashed her front teeth.

“Guts,” which Scholastic released in September, with a print run of one million copies, is her most personal book yet. It tells the story of how, as a child, she developed an intense fear of getting sick and vomiting. It’s a phobia that she still grapples with.

“Illustrating this experience isn’t easy,” she said. “I really have to put myself back into the feeling and my own fear.”

Telgemeier grew up in the San Francisco Bay Area, the eldest of three children. Her parents encouraged her creative streak — she inherited her love of comics from her father, a writer, professor and editor who gave her the dystopian manga series “Barefoot Gen” as a gift.

She started drawing comics when she was 9, copying characters from her favorite animated movies and TV shows and from the comic strips she read in her local newspaper, The San Francisco Chronicle. By the time she was 12 or 13, she settled into her own style, and recorded her experiences in a comics diary, which she kept throughout her teens and early 20s.

At first, drawing was something she did for herself. Later, as a student at New York’s School of Visual Arts, she discovered there was an audience for her work. She started self-publishing and selling mini-comics, mostly autobiographical short stories. In art school, some teachers and fellow students dismissed her illustrations as unsophisticated.

“My style was still rooted in Disney cartoons and the Sunday funnies,” she said. “I got a bit of snooty pushback saying, Well, maybe this is immature.”

But others saw emotional depth and sophistication in her stories. Her work impressed David Saylor, then a creative director at Scholastic, the children’s book publishing house, which was preparing to start an imprint for graphic novels and comics. In 2004, Scholastic hired Telgemeier to illustrate the graphic novel adaptations of Ann M. Martin’s series “The Baby-Sitters Club” for its new imprint, Graphix, then acquired Telgemeier’s graphic memoir “Smile,” which she had been publishing as a web comic.

“Smile” became a No. 1 best seller. The book’s success transformed the graphic novel market and children’s publishing, proving there were young readers who were eager for realistic comics. Her books collectively have more than 18 million copies in print.

“Raina single-handedly created the market for middle-grade graphic memoir,” said Saylor, who is now the publisher of Graphix. “There was a common trope at the time that girls didn’t read comics and that was a boy thing, so the market wasn’t catering to girls and women.”

Telgemeier’s books, with their flawed, funny protagonists and nuanced exploration of the knotty emotional landscape of childhood, changed that.

Her intimate, accessible style and stories about young characters facing everyday struggles with school, family drama, friendships and bullies seem to speak directly to kids.

“If Judy Blume wrote graphic novels, this is what they would look like,” the author Scott Stossel wrote of Telgemeier’s work in the Book Review last month.

Telgemeier followed “Smile” with “Drama,” a graphic novel about kids in a middle school theater club; “Sisters,” a memoir about her tortured relationship with her younger sister; and “Ghosts,” about a lonely, anxious girl whose family moves to a town populated by spirits.

With each book, Telgemeier seemed to be challenging herself and her readers to grapple with more difficult and emotionally revealing material.

“Autobiographical comics require a certain level of courage, and her books get progressively more courageous as she deals with more difficult and embarrassing topics,” said the cartoonist and graphic novelist Gene Luen Yang, who has known Telgemeier since the 1990s, when they were both starting out. “She’s bringing us into her life in a very intimate way.”

In 2016, when she was on tour promoting “Ghosts,” Telgemeier began opening up about her long history of anxiety and panic attacks. When she spoke to young readers at book signings, she would mention that she and a central character in “Ghosts” both suffered from anxiety. “I would let that hang in the air, and people would come up and ask me, What do you mean?” she said.

It was a difficult time in her life, and she had started seeing a therapist again for the first time in 25 years. The previous year, she and her husband had filed for divorce. She started to feel as if her phobias were closing in on her. “It had gotten pretty bad, and I was cutting myself off from a lot of things in my life,” she said.

She started to write a book about the source of her anxiety — an experience she had when she was 9 and caught a stomach flu, which gave rise to an unshakable fear of germs and getting sick. She finished her first draft in about a month.

Telgemeier starts each project by sketching out the pages in pencil, with rough panels, images and text. She does the final artwork on Bristol board, with Col-Erase light blue colored pencil, followed by graphite pencil, which she then she inks over with waterproof India ink so that the images are sharp. Finally, she scans the images into a computer, and a colorist fills in the colors digitally.

The story for “Guts” came together quickly, in part because Telgemeier had been thinking about it for so long.

“I had this story on my mind for a really long time because it’s a story I live every day, but I shied away from it because it’s embarrassing,” she said. “In some ways it’s a simpler book, and in some ways it’s the toughest book I’ve ever written.”

She also decided that her young audience could handle the subject.

“I don’t think I could have told this story any time sooner, but I do think that writing ‘Smile,’ writing ‘Sisters,’ opening myself up and letting readers have access to these memories, gave me the courage to be able to tell this story, because I knew I could trust them,” she said. “I knew they were ready for it. I knew we could have a conversation about it.”

At a recent event to promote “Guts” at a Barnes & Noble in Manhattan, Telgemeier began by telling the audience about her reluctance to write about her stomach problems and anxiety.

“I’ve had to spend my whole life with this, and I’ve avoided talking about this for a really long time,” she said.

She asked the crowd, a packed room full of kids and their parents, if there were things that made them feel afraid, and hands shot up across the room.

After Telgemeier concluded her talk, her young fans pelted her with questions.

“Have you ever thrown up as an adult?” (No.)

“Is it true that you were in a car with a snake?” (Yes.)

“Are you still afraid of snakes?” (Yes.)

“Is your favorite restaurant still Burger King?” (No.)

“Can we be friends?”

In response to that, Telgemeier said that she hoped the girl felt like they were already friends.

“Yes,” the girl said. “I do.”