Hidradenitis Suppurativa: Understanding Painful Nodules and the Rise of Biologic Therapy

Imagine waking up every morning with deep, throbbing pain in your armpits or groin-not from an injury, not from infection you can see, but from something inside your skin that won’t go away. For more than 1 in 50 people, this is daily life with hidradenitis suppurativa (HS). It’s not acne. It’s not a boil. It’s a chronic, inflammatory condition that forms painful nodules, abscesses, and tunnels under the skin, often leaving scars and limiting movement, sleep, and social life. For decades, treatment meant antibiotics, hormonal pills, or surgery. But now, a new wave of targeted drugs called biologics is changing everything.

What Exactly Is Hidradenitis Suppurativa?

HS starts when hair follicles in areas with apocrine sweat glands-like the armpits, groin, under the breasts, and between the buttocks-become blocked. The blockage isn’t from dirt or oil. It’s caused by abnormal skin cell growth and thickening, trapping bacteria and triggering a fierce immune response. The body doesn’t just fight the bacteria; it attacks the surrounding tissue, creating deep, painful lumps that turn into abscesses, drain pus, and form tunnels (sinus tracts) under the skin.

It’s not contagious. It’s not caused by poor hygiene. And it’s not rare. Around 1% to 4% of people worldwide have it, with women affected three times more often than men. Most people first notice symptoms between ages 20 and 29. Many live with it for years before getting a correct diagnosis-some wait over a decade. That’s because doctors often mistake it for recurrent boils or ingrown hairs.

The pain is constant. Not just when the lumps are swollen, but often in the background. People describe it as a deep, burning ache that makes sitting, walking, or even wearing tight clothes unbearable. The emotional toll is just as heavy. Many avoid intimacy, skip the gym, or stop going out altogether because of the odor, drainage, and visible scarring.

Why Traditional Treatments Often Fall Short

For years, the go-to treatments were antibiotics like clindamycin or doxycycline, hormonal therapies like birth control pills or spironolactone, and surgical drainage or removal of affected tissue. These can help in mild cases, but they rarely stop the disease from progressing.

Antibiotics reduce inflammation temporarily but don’t change the underlying immune overreaction. Hormonal treatments help some women, especially those whose HS flares with their cycle, but they don’t work for everyone. Surgery removes visible lesions, but if the disease is still active underneath, new nodules form nearby. Many patients end up with multiple surgeries, scarring, and no real long-term relief.

The real problem? These treatments don’t target the root cause: the runaway inflammation. HS isn’t just a skin problem-it’s a systemic immune disorder. That’s why biologics, which were first developed for conditions like psoriasis and rheumatoid arthritis, became such a game-changer.

How Biologic Therapy Works

Biologics are made from living cells and designed to block specific parts of the immune system that drive inflammation. Unlike antibiotics or steroids that suppress the whole immune system, biologics are like precision missiles-they hit only the targets causing the damage.

In HS, three key inflammatory molecules are overactive: TNF-alpha, IL-17A, and IL-17F. These cytokines act like alarm bells, telling immune cells to attack healthy tissue. Biologics silence those alarms.

There are now three FDA-approved biologics for HS:

• Adalimumab (Humira): Blocks TNF-alpha. First approved in 2015. Given as a weekly or every-other-week injection. About 42% of patients see at least half their lesions improve within 12 weeks.
• Secukinumab (Cosentyx): Blocks IL-17A. Approved in early 2024. Given as monthly injections after an initial weekly dose. In trials, 45% of patients achieved major improvement at 16 weeks.
• Bimekizumab (BIMZELX): Blocks both IL-17A and IL-17F. Approved in mid-2024. This dual-action approach is the most potent so far, with 67% of patients seeing 50% or more lesion reduction at 16 weeks.

These aren’t just numbers. Real patients report life-changing results. One woman from Perth, who’d been on antibiotics for six years with no relief, started secukinumab and saw her abscesses disappear within five weeks. Another man with HS since his teens said he slept through the night for the first time in 15 years after starting bimekizumab.

Comparing the Biologics: Efficacy, Cost, and Side Effects

Not all biologics are the same. Here’s how they stack up:

Bimekizumab shows the strongest results, especially for people with lots of inflamed nodules. But adalimumab still has a place-especially for those with advanced scarring and sinus tracts. Secukinumab strikes a balance between effectiveness and tolerability.

Cost is a huge barrier. In the U.S., monthly prices range from $5,800 to $6,900. Even with insurance, many patients pay $800-$1,200 out of pocket. Medicaid patients face approval rates as low as 45%, while those with private insurance get approved about 80% of the time. In Australia, PBS subsidies are limited, and access varies by state. Many patients rely on patient assistance programs from drugmakers to afford treatment.

Who Benefits Most-and Who Doesn’t

Biologics work best for people with Hurley Stage II or III HS:

• Stage II: Multiple abscesses and sinus tracts, but not fully connected.
• Stage III: Widespread, interconnected tunnels and abscesses, often with heavy scarring.

They’re less effective in Stage III patients with heavy, long-standing scarring. That’s because biologics reduce inflammation, but they can’t undo scar tissue. That’s why experts stress: start early.

People with other autoimmune conditions-like psoriasis or Crohn’s disease-often respond better to biologics because their immune systems are already primed to react to these drugs.

But not everyone is a candidate. You can’t start biologics if you have:

• Active tuberculosis
• Chronic hepatitis B or C
• Uncontrolled heart failure
• A recent serious infection

Before starting, you’ll need blood tests, a TB skin test, and a review of your medical history. Your doctor will also check your vaccination status-you need to be up to date on shingles, pneumonia, and flu shots.

What Happens After You Start?

Most people see some improvement within 4 to 8 weeks. But it takes 12 to 16 weeks to know if the drug is working well enough. Doctors use the IHS4 score-a tool that counts abscesses, nodules, and draining tunnels-to track progress.

If you’re not improving by week 12, your doctor may switch you to another biologic. About 30% of people who don’t respond to adalimumab do respond to secukinumab or bimekizumab.

Side effects are usually mild: redness or itching at the injection site, headaches, or minor colds. But because biologics suppress part of the immune system, you’re at higher risk for serious infections like pneumonia or tuberculosis. That’s why regular check-ins with your dermatologist are critical.

Interestingly, many patients see improvements in their cholesterol levels too. Triglycerides drop, HDL (the good cholesterol) rises. This suggests biologics aren’t just helping the skin-they may be reducing long-term heart disease risk, which is higher in HS patients.

Real Stories, Real Challenges

On patient forums like MyHSteam and Reddit, people share what really happens:

• “After 10 years of pain, adalimumab gave me back my life. But I had to quit my job to manage the injections and doctor visits.”
• “I started bimekizumab and saw my abscesses vanish in 6 weeks. Then I got a yeast infection and had to pause treatment.”
• “I can’t afford it without insurance. I’m on a waiting list for a patient assistance program.”
• “I stopped because the cost was too high. Now I’m back to antibiotics and painkillers.”

Many say the biggest win isn’t just fewer lumps-it’s being able to wear shorts again, hug their kids without fear, or sleep through the night.

But the emotional burden doesn’t vanish overnight. Some feel guilt for not being “grateful enough” for treatment. Others feel isolated when friends don’t understand why they can’t just “take a pill.”

What’s Next? The Future of HS Treatment

The field is moving fast. Three new biologics are in late-stage trials:

• Guselkumab: Targets IL-23. Early results show 58% response rate.
• Spesolimab: Blocks IL-36. Shows promise for patients who didn’t respond to IL-17 inhibitors.
• TAK-279: A new oral drug that blocks TYK2, a key immune signaling molecule.

Some researchers are even exploring combination therapy-using biologics alongside minor surgical procedures to remove stubborn tunnels. One study showed 89% of patients responded when biologics were paired with surgical cleaning, compared to 67% with biologics alone.

And there’s hope for personalized treatment. A 2024 study identified a 12-gene signature that can predict who will respond to adalimumab with 85% accuracy. That means in the future, you might get a blood test before starting treatment to know which drug will work best for you.

By 2030, experts predict 70% of moderate-to-severe HS patients will be on biologics. Right now, it’s about 28%. The gap is closing-but only if access improves.

What You Can Do Now

If you think you have HS:

1. See a dermatologist who knows HS. Don’t settle for a general practitioner who calls it “recurrent boils.”
2. Ask about your Hurley stage. That determines your treatment options.
3. Start biologics early. The sooner you treat the inflammation, the less scarring you’ll get.
4. Stop smoking. Smoking makes HS worse and reduces biologic effectiveness.
5. Manage your weight. Even a 10% weight loss can reduce flare-ups.
6. Join a support group. You’re not alone. Communities like the HS Foundation and MyHSteam offer real advice and emotional support.

HS is not your fault. It’s not something you caught. It’s a complex immune condition that’s finally being understood-and treated-in ways that work.

Biologics aren’t a cure. But for the first time, they offer real control. They turn a life of pain and isolation into one of manageable symptoms and restored dignity.