Opioid withdrawal produces a predictable set of physical and psychological symptoms that many people compare to a severe case of the flu. Symptoms typically begin within 12 to 30 hours of the last dose, depending on the type of opioid, and peak around 48 to 72 hours. While intensely uncomfortable, most acute withdrawal symptoms resolve within a week for short-acting opioids, though longer-acting ones can stretch the timeline considerably.
Early Symptoms: The First 24 Hours
The earliest signs of withdrawal tend to feel like the beginning of a bad cold. Your eyes start watering, your nose runs, and you yawn repeatedly. Muscle aches set in, often described as a deep soreness in the legs and back. Anxiety builds quickly, sometimes before the physical symptoms are fully noticeable, and many people report an intense, almost overwhelming craving for opioids during this window.
Other early symptoms include sweating that seems out of proportion to the temperature, difficulty sleeping, restlessness that makes it hard to sit still, and a general sense of agitation. Your pupils may appear noticeably larger than usual, and your heart rate and blood pressure tend to climb. These changes happen because opioids normally suppress your body’s stress-response system. When the drug is removed, that system rebounds hard, flooding you with norepinephrine, the chemical behind the “fight or flight” response.
Peak Symptoms: Days Two and Three
The most difficult stretch typically hits between 48 and 72 hours after the last dose. This is when gastrointestinal symptoms become dominant. Nausea, vomiting, diarrhea, and abdominal cramping can be severe and persistent. Goosebumps appear across the skin, sometimes in waves. Chills and fever alternate with heavy sweating. The combination of not eating, vomiting, and diarrhea can leave you feeling completely drained.
Insomnia often worsens during this phase. Even when exhausted, your body may jolt you awake with leg cramps or a racing heart. Sensitivity to light can make bright environments painful. The psychological weight of this period is significant: anxiety, irritability, and low mood are nearly universal, layered on top of physical misery and strong drug cravings.
Short-Acting vs. Long-Acting Opioids
The timeline varies based on which opioid your body is dependent on. With short-acting opioids like heroin or immediate-release prescription painkillers, symptoms usually start within 8 to 12 hours of the last use, peak around day two or three, and begin improving by days five through seven.
Long-acting opioids like methadone follow a slower schedule. Symptoms may not appear until 30 hours or more after the last dose, and the overall withdrawal period stretches longer, sometimes lasting two to three weeks before fully resolving. The intensity of withdrawal also depends on how much you were taking, how long you used it, and your individual biology.
Why Withdrawal Feels So Intense
Opioids work partly by quieting a region of the brain that controls the body’s alarm system. With regular use, this region adapts to the presence of the drug and dials up its baseline activity to compensate. When opioids are suddenly removed, that region fires at abnormally high rates, releasing a surge of stress hormones and activating the sympathetic nervous system. This is what drives the sweating, racing heart, elevated blood pressure, diarrhea, and anxiety. Essentially, your body is stuck in an exaggerated stress response until it recalibrates to functioning without the drug.
When Withdrawal Becomes Dangerous
Opioid withdrawal is often described as not life-threatening, and for most people receiving appropriate support, that’s true. But persistent vomiting and diarrhea can cause severe dehydration, dangerously elevated blood sodium levels, and in extreme cases, heart failure. This risk is highest for people withdrawing without medical oversight, particularly in settings like jails or at home without access to fluids and electrolytes. The discomfort alone also drives many people to resume opioid use, which carries its own serious risk: tolerance drops rapidly during even a short period of abstinence, making a previously “normal” dose potentially fatal.
Post-Acute Withdrawal: The Longer Tail
After the acute phase passes, many people enter a prolonged period sometimes called post-acute withdrawal. This phase is less about physical misery and more about mood and mental function. Common symptoms include persistent anxiety, depression, irritability, difficulty concentrating, fatigue, disrupted sleep, a flat or joyless feeling, and ongoing cravings. These symptoms are typically most intense during the first four to six months of abstinence and gradually diminish over time, though for some people they linger for a year or longer. Understanding that this phase is a normal part of recovery, not a personal failing, can make a real difference in staying the course.
Withdrawal in Newborns
Babies born to mothers who used opioids during pregnancy can experience their own form of withdrawal, called neonatal abstinence syndrome. The hallmark presentation is a combination of increased muscle tone, tremors while at rest, and an exaggerated startle reflex. These infants often cry at a notably high pitch, are difficult to console, sneeze frequently, and have trouble feeding. Diarrhea, sweating, rapid breathing, and unstable body temperature are also common. Symptoms are assessed using a scoring system, and treatment is initiated when scores indicate significant withdrawal. Seizures can occur, though they are rare and most associated with methadone exposure.
How Symptoms Are Managed
Treatment for opioid withdrawal focuses on two goals: reducing the intensity of symptoms and preventing complications. Clinicians use an 11-item assessment tool that tracks things like pulse rate, pupil size, sweating, restlessness, gut symptoms, tremor, yawning, goosebumps, joint aches, anxiety, and nasal or eye symptoms to gauge severity and guide treatment decisions.
The core approach involves medications that calm the overactive stress-response system driving most withdrawal symptoms. These work by dampening the flood of norepinephrine responsible for the sweating, anxiety, diarrhea, and racing heart. For specific symptoms, treatment is straightforward: anti-nausea medication for vomiting, over-the-counter pain relievers for muscle and joint aches, and anti-diarrheal medication for gut symptoms. Hydration is critical throughout, especially during the peak phase when fluid loss from vomiting and diarrhea is highest.
Many treatment programs also offer medications that act on the same brain receptors as opioids but in a controlled, longer-acting way. These can dramatically reduce withdrawal severity, ease cravings, and serve as a bridge to longer-term recovery. For most people, medically supported withdrawal is significantly safer and more tolerable than attempting to stop on your own.