At 61, character actress Jenifer Lewis is radiant and agile. She’s been playing the take-no-prisoners grandmother Ruby Johnson to great acclaim for 3½ seasons on ABC’s hit sitcom “Black-ish.”

Her new memoir, “The Mother of Black Hollywood,” gets its name from the myriad roles in which she has played mom — to Angela Bassett (as Tina Turner), Taraji P. Henson, Whitney Houston, Tupac Shakur and several other superstars.

The book’s subject matter, however, lies much more with bipolar disorder, with which she was diagnosed in 1990.

Lewis resisted the diagnosis at first and refused to take medication until a self-described nervous breakdown left her convulsing in sobs, a hostage to her untreated neurochemistry. A quarter-century later, she is thriving and happy because, as she says, she “does the work.” She takes her medication daily, was in therapy for nearly two decades, and still occasionally checks in for fine-tuning. She routinely hikes, does Pilates, and eats and drinks healthfully. (But she does allow for splurges. One of the book’s funnier anecdotes involves eating creme brulee for breakfast on vacation.)

She has made educating others about bipolar disorder a huge part of her life’s work. Following is a transcript of a conversation with her, edited for clarity and length.

Q: In your memoir, you’re wonderfully candid about your bipolar disorder. And instead of devoting one chapter to it or compartmentalizing it, you weave your bipolarity throughout the entire book. Why did you decide to tell your story this way?

A: It’s like I always say, “There ain’t no shame in my game.” When I was first diagnosed bipolar in 1990, I was, like, “What? Bipolar? I’m bicoastal, but what’s this ‘bipolar’?” [Laughs.] If you say, “Jenifer, you’re crazy!” hell, I always knew that. I’d heard, “Jenny, you’re crazy!” my whole life. [Laughs.]

And it was hard. It took me four years after my diagnosis to start taking medication. I thought, “I’m fine.” And in my work, in my one-woman shows in particular, I used the mania to my advantage. Oh! That electricity onstage!

But afterward, offstage, I just got tired. I got so tired. The crying, and I didn’t know why. It was a very dark place. But really, my therapist gave a name to how I’ve been all my life. . . . I wrote one of my one-woman shows about it, “Bipolar, Bath, and Beyond.” [Laughs.] You’ve got to work hard each day. There are no shortcuts to getting better. Or to anything in life. You absolutely have to work at it. Go to therapy. Take your meds. Take care of yourself. Don’t eat or drink alone in the dark. Live your life.

My therapist says, “You did it! You did it kickin’ and screamin’, but you did it.” But no one gets it right the first time. Or the second or third time. You’ve got to stay at it. You better get up and stay up. You’ve got to do the work.

Q: Do you think you’d have the career you have right now if you hadn’t gotten help?

A: Oh, girl. No, no, no. Come on. [Laughs.] I’d be lying in a gutter somewhere. I’d be dead. It’s dangerous not to get help. I wouldn’t be where I am today if I hadn’t gotten help. You reach a point where you don’t want to wake up and feel depressed like that again. You don’t want to feel tired like that. Unfortunately, as people, we usually reach that point before we seek help.

I wanted to keep working. I’ve always loved my work. From the first time I had a solo in church when I was 5, I knew I was an entertainer. Oh, that applause! To keep working, I had to get help. And I’m grateful every day for the encouragement I’ve gotten and for the help I receive. That’s why the acknowledgments section in the book is so long. I don’t want to leave out anyone.

I’m so grateful. Life can still be hard sometimes, but I wake up with a smile. And I know what it’s like to wake up crying. Now, I find such pleasure in colors, in flowers, in children’s eyes. And I think, “Here am I.”

Q: You’re a longtime AIDS activist, you march for Black Lives Matter, for women. You’ve often said we can’t just fight on behalf of ourselves, but on behalf of one another.

A: That’s part of why I wanted to tell my story now for the millennials. It’s very important for me to give them my story. They’ve honored all those in the civil rights movement at the front of the line, those who took the fire hoses, who took the dogs. They stood up and they’ve stayed up. So I tell it all, so that they might learn from it. I ain’t telling no lies. This is my story. I don’t keep secrets. We’re only as sick as our secrets. I don’t tell lies. I tell the truth. I lay it all on the slab. [Laughs.]

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