There was a time when Chuck Panozzo didn’t ever think he’d stand on stage again.

The co-founder and bassist of Styx, the band responsible for a U-Haul worth of lighter-waving hits such as “Come Sail Away,” “Renegade,” “Don’t Let It End” and “Show Me the Way,” was diagnosed with AIDS in 1998. Two years earlier, his twin brother, Styx drummer John, died at age 47 from gastrointestinal bleeding related to alcohol abuse.

It was hardly the best of times for the musician.

But as the years passed, Panozzo began to occasionally rejoin the relentlessly touring lineup of veteran guitarist/singers James “J.Y.” Young and Tommy Shaw; Todd Sucherman, the band’s drummer since 1995; Lawrence Gowen, Styx’s singer/keyboardist since 1999; and Ricky Phillips, its full-time bassist since 2003.

Last year, Panozzo, 62, performed in nearly all of Styx’s 107 shows and he recently returned from an extensive tour of the United Kingdom and Sweden.

Will he be onstage Thursday at Styx’s co-headlining show with Yes at the Verizon Wireless Amphitheatre in Alpharetta?

Barring any unforeseen problems, most definitely.

“This year my attitude is, I’m out to perform as many shows as I can. If something happens, Ricky [Phillips] is my guy. But it’s great for the fans, it’s great for me and it makes the band look good. We’re all onstage to support each other,” Panozzo said recently from his home in Fort Lauderdale, Fla., where he moved about a decade ago from his native Chicago.

As often happens with age, things resonate differently with Panozzo now.

When he performs “Angry Young Man” with the band, it isn’t – obviously -- about teenage angst anymore, but about realizing, he said, “No one is going to pick you up until you pick yourself up.”

And when he hears thousands and thousands of fans singing along to the indelible chorus of “Come Sail Away"? Panozzo pauses briefly, unsure of how to describe the feeling, and then determines, “I just love it.”

In 2007, six years after he publicly announced he was gay and living with AIDS, Panozzo released his autobiography, “The Grand Illusion: Love, Lies and My Life with Styx.”

The book detailed Panozzo’s love affair with music and his struggles as a closeted gay man and was not, as some might have expected, a salacious tell-all.

“It got great reviews, so ha ha, English teachers!” Panozzo said gleefully.

The bassist, who is active with several AIDS organizations, chose not to use his literary soap box to castigate Dennis DeYoung, Styx’s original singer and a childhood friend of the Panozzo brothers.

Though Styx maintains a contentious relationship with DeYoung, even removing references to him in the band history section of its official website earlier this year, Panozzo approaches the situation philosophically while confirming that he doesn’t have any communication with the voice behind Styx's biggest ballads.

“We don’t have any reason to speak to each other at this point in our lives,” he said. “I’m too old to carry grudges and I don’t have time to waste on nonsense. But it’s really just, sometimes you can’t live together anymore, you know? You don’t hate the person, but if you can be with each other and be productive, then what’s the point?”

Panozzo’s productivity extends to Styx’s “Regeneration Volume 2” CD, which the band planned to have ready for sale during this tour, which launched July 5.

For him, playing bass on reworked versions of “Blue Collar Man” and “Snowblind” was effortless, but he was impressed by the work ethic of the newer Styx members to learn the intricacies of the classic songs.

For now, though, Panozzo is relishing the opportunity to play live again.

“I’ve got the only job,” he said, “where I go to work and get a standing ovation.”

Concert preview

Styx and Yes

7 p.m. Thursday. $19-$99. Verizon Wireless Amphitheatre at Encore Park, 2200 Encore Parkway, Alpharetta. 1-800-745-3000, www.ticketmaster.com.