Cotton Fever Guide: Symptoms, Causes, Treatment & Prevention

   Oct. 17, 2025
   4 minute read
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Last Edited: October 17, 2025
Author
Claudia Rose
Clinically Reviewed
Edward Jamison, MS, CAP, ICADC, LADC
All of the information on this page has been reviewed and certified by an addiction professional.

Cotton fever can hit minutes after an injection and feel like the worst flu of your life—sudden chills, pounding head, and a racing heart. People who inject opioids sometimes mistake it for a simple bug, but it can mimic dangerous infections. Knowing the cotton fever symptoms and what to do next can keep a tough day from turning into a medical emergency. As Ralph Waldo Emerson said, “The first wealth is health.” In a nation where drug deaths top 100,000+ per year and emergency rooms see rising complications from injection-related substance abuse, taking symptoms seriously is a must.

Cotton Fever Symptoms: What It Feels Like

Most people describe a sudden “wall of sickness” shortly after an injection—often within 15 minutes to a few hours. Common signs & symptoms include:

  • Fever (often 101–104°F), chills, sweats
  • Fast heart rate, fast breathing, shaking
  • Headache, body aches, back pain
  • Nausea, vomiting, stomach cramps, general weakness
  • Anxiety or a sense that “something is really wrong”

Symptoms tend to peak quickly and, in many cases, ease over 6–24 hours with rest, fluids, and fever reducers. But here’s the catch: cotton fever can look a lot like sepsis, pneumonia, or heart-valve infection (endocarditis). Because those are life-threatening, err on the side of safety—especially if fever is very high, you feel confused, you’re short of breath, or the symptoms don’t improve.

What Causes Cotton Fever (and Why It Happens)

The name comes from using bits of cotton or cigarette filters to strain drug solutions. Cotton fibers, bacteria, or bacterial endotoxins can trigger a strong immune reaction when they enter the bloodstream. Your body responds with fever, inflammation, and those dramatic flu-like symptoms. Reusing old cottons, using non-sterile water, or drawing up through contaminated supplies raises risks.

Important reality check: even if a case turns out to be “just” cotton fever, repeated injections raise the odds of serious infections like skin abscesses, bloodstream infections, endocarditis, and hepatitis. Hospitalizations for these conditions have increased in many communities. Bottom line—don’t ignore a high fever after injecting.

When to Seek Care & How Doctors Treat It

Go to the ER or urgent care now if you have:

  • Fever with severe pain, confusion, chest pain, or shortness of breath
  • A fever that doesn’t start improving in 6–12 hours
  • Red, hot, or swollen injection sites; streaking redness; pus
  • A new heart murmur or fainting spells

What to expect at the clinic or ER:

  • Vitals, exam, and lab tests (blood counts, cultures) to rule out serious infection
  • Possible urine tests, chest X-ray, or EKG based on your symptoms
  • Fluids, fever control, nausea medicine, and observation
  • If the team suspects bacterial infection, they may start antibiotics while cultures are pending

If serious infection is ruled out, cotton fever usually improves with supportive treatment. Still, your care team may recommend follow-up in 24–48 hours to be safe, especially if you have heart disease, are pregnant, or have a weakened immune system.

symptoms of cotton fever infographic

Prevention, Recovery & Long-Term Help

Simple steps that reduce harm (while you work on bigger goals):

  • Don’t reuse cottons or filters; avoid makeshift filters like cigarette butts.
  • Use sterile water and new, sterile supplies every time.
  • Clean hands and skin before any injection; never share equipment.
  • Watch for early signs & symptoms of infection: redness, warmth, swelling, drainage, fever.

But the safest prevention is change. If injecting is part of your life, you don’t have to do it alone. Evidence-based care can help you stop and stay stopped:

  • Medical evaluation & detox: Same-day assessments, comfort medications, and stabilization if you’re experiencing withdrawals or medical complications.
  • Medications for opioid use disorder (MOUD): Buprenorphine or methadone cut cravings and reduce overdose risk.
  • Rehab levels of care: Residential, PHP/IOP, or outpatient rehab with counseling (CBT/DBT), trauma-informed care, relapse-prevention skills, and recovery support.
  • Insurance & access: Many programs are insurance accepted rehab providers—we’ll help verify benefits so cost isn’t a barrier.

Your next step: Search our national directory for detox, MOUD, and rehab options—or call (866) 578-7471 now for confidential, judgment-free help.

Feature a True Stories of Addiction Video

Steven got involved in drug use when he was very young. Throughout his adult life, he continued to struggle with his drug addiction. He quickly spiraled down after losing his job over a drug charge. After his family started to intervene and tried to get him help, he decided to go to rehab and found recovery. “One fever changed everything. Watch how medical care, medication, and community support helped me move from crisis to recovery.”

Frequently Asked Questions
Can you die from cotton fever?
Death from true cotton fever is rare, but the danger is missing a serious infection that looks the same (sepsis, pneumonia, endocarditis). If fever is very high, symptoms are severe, or not improving, go to the ER. When in doubt, get checked.
How do you get rid of cotton fever fast?
There’s no instant cure. Most cases ease within 6–24 hours with rest, fluids, and fever reducers. Do not inject more to “feel better.” If symptoms are severe, you have chest pain or confusion, or nothing improves by 6–12 hours, seek urgent care.
What does cotton fever look like?
Sudden flu-like illness shortly after an injection: fever and chills, shaking, sweaty skin, fast heartbeat and breathing, weakness, and sometimes vomiting. It often hits within minutes to a few hours after using.
What bacteria causes cotton fever?
It’s often linked to endotoxins from gram-negative bacteria found on cotton plant fibers (commonly described in the Enterobacter/Pantoea family) or contaminated water/supplies. The reaction can be toxin-driven rather than a full bloodstream infection—but the symptoms can look similar.
How long does cotton fever last?
Typical duration is 6–24 hours, sometimes up to a day or two. If symptoms are not improving after 6–12 hours—or you develop severe pain, shortness of breath, confusion, or fainting—go to the ER to rule out dangerous infections.
What does cotton fever feel like?
Like a sudden, severe flu: chills, shaking, pounding head, body aches, back pain, nausea, and an intense “something is really wrong” feeling. The onset is usually quick after the injection.
How do you treat cotton fever?
Supportive care—fluids, rest, fever and nausea control—while a clinician rules out serious infection. In clinics/ERs, you may receive labs, cultures, and observation; antibiotics may be started if infection is suspected. Follow-up in 24–48 hours is common.
What are the symptoms of cotton fever?
Fever (often 101–104°F), chills/sweats, rapid heart rate, rapid breathing, headache, muscle aches, fatigue, nausea/vomiting, and anxiety. Red or painful injection sites, streaking redness, or pus point more toward skin/soft-tissue infection and need prompt care.
What causes cotton fever?
Reusing cottons or cigarette filters, drawing through old filters (“re-cooking”), using non-sterile water, and handling equipment with unwashed hands. Any step that lets bacteria or endotoxins into the solution raises risk.
When should I go to the ER?
Go now if you have severe chest pain, trouble breathing, confusion, a very high or persistent fever, signs of dehydration, a heart murmur, fainting, or any seizure activity. Also go if symptoms haven’t improved within 6–12 hours or you’re pregnant/immunocompromised.
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