A dog bite causes immediate tissue damage and carries a real risk of infection, even when the wound looks minor. What happens next depends on how deep the bite is, where it landed on your body, and how quickly you clean and treat it. Most dog bites heal without serious complications when handled properly, but some develop infections within 24 hours, and a small number lead to dangerous systemic illness.
The Wound Itself
Dogs bite with significant jaw pressure, so the damage is often a combination of wound types. A bite can create puncture wounds from the canine teeth, lacerations where the skin tears, and crush injuries to the underlying tissue. Punctures are deceptive because the entry point looks small while the damage extends deeper into muscle or fat. Lacerations, where the skin is visibly torn open, bleed more but are actually easier to clean, which lowers infection risk.
Crush injuries happen because a dog’s jaw compresses tissue rather than slicing it cleanly. This means even bites that don’t break the skin can cause bruising, swelling, and damage to the tissue underneath. When the skin does break, the combination of crushing and puncturing creates pockets where bacteria can thrive, sealed off from air and difficult to flush out.
What to Do Immediately
The single most important thing after a dog bite is thorough cleaning. Wash the wound with soap and water for several minutes, using enough pressure and volume to flush out debris and bacteria. In a clinical setting, medical staff irrigate bite wounds with at least 250 mL of saline pushed through a syringe to create pressure. At home, running tap water over the wound while gently washing with soap is the practical equivalent. The goal is to physically remove as much bacteria as possible before it establishes itself in the tissue.
After cleaning, apply a clean bandage and get to a doctor, especially if the bite is deep, on your hand or face, or if you can’t confirm the dog’s vaccination status. Bites on the hands are particularly infection-prone because of the tendons, joints, and limited blood supply in that area.
How Infection Develops
Dog mouths harbor a mix of bacteria that don’t normally live on human skin. The most common culprits include Pasteurella species and a group of bacteria called Capnocytophaga, along with various staph and strep bacteria. When a bite drives these organisms deep into your tissue, your immune system may not clear them before they multiply.
Signs of infection from a dog bite typically appear within about 24 hours. You’ll notice increasing redness spreading outward from the wound, swelling, warmth to the touch, and throbbing pain that gets worse rather than better. Some infected bites develop pus or discharge, and you may run a fever. If redness is spreading visibly or you develop a fever, that’s a sign the infection is moving beyond the wound itself into the surrounding tissue.
The standard preventive treatment is a course of antibiotics lasting three to seven days, typically started before infection sets in for bites that are deep, on the hands, or in people with weakened immune systems. Not every dog bite requires antibiotics, but your doctor will assess the wound’s depth, location, and contamination level to decide.
Capnocytophaga: A Rare but Serious Risk
One bacterium worth knowing about is Capnocytophaga canimorsus, which lives in the mouths of most healthy dogs. For the vast majority of people, exposure causes no problems. But in certain individuals, it can cause a rapidly progressing infection that leads to sepsis, organ failure, and in severe cases, amputation or death.
Symptoms typically begin three to five days after the bite and include blisters around the wound, fever, vomiting, diarrhea, headache, and confusion. The infection can escalate from mild to life-threatening within hours in high-risk individuals. About 60 percent of Capnocytophaga infections occur in people with specific risk factors: a weakened immune system from cancer treatment or chronic disease, a history of heavy alcohol use, diabetes, or a missing spleen. People without a spleen face 30 to 60 times the normal risk of dying from this infection and can progress to organ failure within 24 to 72 hours of the first symptoms.
Tetanus and Rabies
Dog bites are classified as “dirty wounds” for tetanus purposes because they involve saliva. If you’ve completed your tetanus vaccine series and your last booster was less than five years ago, you don’t need another one. If it’s been five or more years, or if your vaccination history is incomplete or unknown, you’ll need a booster.
Rabies is rare in domestic dogs in the United States but remains a concern, especially with stray or unvaccinated animals. If rabies can’t be ruled out, post-exposure treatment involves a series of steps: thorough wound cleaning, an injection of rabies antibodies (ideally around the wound itself), and then a series of four vaccine doses spread over two weeks, given on the day of the bite and again on days 3, 7, and 14. This is not the painful series of stomach injections from decades past. The shots go in the arm and are comparable to a flu shot in terms of discomfort.
People with compromised immune systems receive a fifth dose on day 28 to ensure adequate protection.
Stitches Are Not Always the Answer
Unlike a clean surgical cut, bite wounds present a dilemma when it comes to closure. Stitching a bite shut can trap bacteria inside the wound, creating an ideal environment for infection. The World Health Organization recommends delayed closure for bite wounds, meaning doctors often leave them open initially, let them drain, and close them later once the risk of infection has passed. Bites on the face are sometimes an exception because of cosmetic concerns and the face’s rich blood supply, which helps fight infection.
If your bite wound is left open, it will heal from the inside out over days to weeks, depending on depth. Your doctor may pack the wound with gauze and have you return for regular dressing changes.
What Happens With Animal Control
Most jurisdictions require dog bites to be reported, and the process that follows is primarily about ruling out rabies. A local authority will typically investigate the bite and arrange for the dog to be observed. For domestic dogs, cats, and ferrets, the standard protocol is a 10-day quarantine period that starts from the time of the bite. If the dog is healthy at the end of those 10 days, it did not transmit rabies. The quarantine can sometimes happen at the owner’s home if the dog is vaccinated, wasn’t a stray, and the owner can provide a secure enclosure and monitor the animal’s behavior.
The biting dog’s owner is generally responsible for the cost of quarantine. If the dog is euthanized or dies during the observation period, its brain tissue is tested for rabies directly. This reporting system exists to protect both you and the broader community, so even if the bite seems minor, letting your local animal control know is an important step.
Recovery Timeline
A minor dog bite that doesn’t become infected typically heals within one to two weeks. Deeper wounds, especially those left open to heal on their own, can take several weeks and may require follow-up visits for wound checks and dressing changes. Infected bites add time to recovery, depending on how quickly the infection is caught and treated.
During healing, watch for the warning signs of infection daily: worsening pain after the first day or two, expanding redness, streaks radiating from the wound, pus, fever, or swollen lymph nodes near the bite. These signs are most likely to appear in the first 24 to 72 hours, but infections can develop up to a week or more after the bite. Bites on the hands, feet, and over joints tend to heal more slowly and are more prone to complications because of the complex structures underneath.