A dog bite can range from a minor scrape to a serious wound that damages nerves, tendons, or blood vessels. What happens next depends on how deep the bite is, where it landed on your body, and how quickly you clean and treat it. Even bites that look small on the surface can introduce dangerous bacteria deep into tissue, making infection the most common complication.
Clean the Wound Right Away
The single most important thing you can do after a dog bite is wash it thoroughly. Use mild soap and run warm tap water over the wound for five to ten minutes. This extended rinse helps flush out bacteria from the dog’s mouth before they can establish an infection. If the wound is bleeding, slow it with a clean cloth, then apply an over-the-counter antibiotic cream and cover it with a sterile bandage.
Even after cleaning, you should have the bite evaluated by a medical professional. Dog teeth can push bacteria deep into puncture wounds where surface cleaning can’t reach. Change the bandage several times a day and watch closely for early signs of infection: increasing redness, swelling, warmth around the wound, worsening pain, or fever.
Why Dog Bites Get Infected So Easily
Dog mouths carry several types of bacteria that can cause serious infections in humans. The two most notable are Pasteurella, which is found in the mouths of most dogs and can cause a rapidly developing skin infection, and Capnocytophaga, a group of bacteria that can lead to severe illness, particularly in people with weakened immune systems. These bacteria thrive in the warm, low-oxygen environment created by a puncture wound.
Puncture wounds are more infection-prone than open lacerations because the skin seals over the top while bacteria multiply underneath. Bites to the hands carry especially high infection risk because the hand contains many small compartments, tendons, and joints where bacteria can spread quickly with limited blood flow to fight them off. The Infectious Diseases Society of America specifically highlights hand wounds as a priority for preventive antibiotics, typically a three-to-five-day course prescribed for high-risk bites.
Low-risk bites, like shallow scrapes on well-vascularized areas, don’t always require antibiotics. Yet studies show that over 90% of dog bite patients receive an antibiotic prescription regardless of risk level, suggesting many doctors err on the side of caution.
Signs of Infection to Watch For
Most bite infections become apparent within 24 to 72 hours. The first signs are redness and swelling that expand beyond the immediate wound edges, along with increasing tenderness and warmth. You may notice red streaks extending outward from the bite, which signals that the infection is spreading through surrounding tissue, a condition called cellulitis.
If infection progresses beyond the skin, you can develop fever, chills, fatigue, and swollen lymph nodes near the bite. In rare cases, bacteria enter the bloodstream and cause a body-wide response. People who are immunocompromised, take medications that suppress the immune system, or have liver disease face a higher risk of these severe outcomes from Capnocytophaga and other bite-related bacteria.
Deep Bites Can Damage Nerves and Tendons
A strong bite doesn’t just break the skin. Dog jaws can generate enough force to crush underlying structures, especially in the hands, fingers, and forearms. Research on dog bites to the upper extremities found that when doctors identified nerve problems during a physical exam (numbness, loss of sensation, or inability to move a finger normally), surgical exploration confirmed actual nerve damage about 69% of the time. For tendons, the confirmation rate was 77%. When a blood vessel exam was abnormal, surgical exploration found arterial injury 100% of the time.
If you notice numbness, tingling, inability to bend or straighten a finger, or heavy bleeding that won’t stop with pressure, the bite likely damaged something deeper than skin. These injuries often require surgical repair, and outcomes improve when they’re identified early rather than days later.
Stitches Aren’t Always the Right Call
Unlike a clean cut from a knife, dog bites are crushing, tearing wounds contaminated with bacteria. Stitching them closed immediately can trap bacteria inside and increase infection risk. For this reason, the World Health Organization recommends postponing suturing of bite wounds as a measure to prevent infection.
Doctors generally consider closing a bite wound with stitches when it’s on the face (which has excellent blood supply and heals well), when it’s less than eight hours old, and when it shows no signs of infection at the time of treatment. Puncture wounds, infected wounds, and bites older than eight hours are typically left open to heal from the inside out. Facial lacerations longer than about two centimeters often get stitched for cosmetic reasons, but even then, doctors may delay closure for a few hours if rabies immunoglobulin needs to be administered first.
Rabies and Tetanus Vaccines
Rabies is rare in domesticated dogs in the United States, but it’s nearly always fatal once symptoms appear, so doctors take it seriously. If the dog that bit you is unknown, stray, or behaving strangely, you’ll likely be started on post-exposure rabies prevention. This involves four vaccine injections given over two weeks: one immediately, then additional doses on days 3, 7, and 14. People with compromised immune systems receive a fifth dose on day 28. If you’ve been vaccinated against rabies previously, you only need two doses, three days apart.
If the dog’s owner can confirm it’s up to date on rabies vaccines, the risk drops significantly. Animal control may still quarantine the dog for observation, typically for ten days, to confirm it doesn’t develop rabies symptoms.
Tetanus is the other vaccine concern. The bacteria that cause tetanus live in soil and can enter through any break in the skin. If your last tetanus booster was more than ten years ago, or if you can’t remember when you had one, a dog bite is a clear reason to get updated. Adults need a tetanus booster every ten years to maintain protection.
What Medical Treatment Looks Like
When you arrive for medical care, expect the provider to irrigate the wound more thoroughly than you could at home, often using a syringe to flush saline deep into puncture wounds. They’ll examine the area for signs of nerve, tendon, or vascular damage, checking your sensation, finger movement, and blood flow beyond the wound.
For high-risk bites (puncture wounds, hand or foot bites, bites in immunocompromised patients), you’ll likely leave with a short course of preventive antibiotics. The provider will also assess your need for rabies prevention and a tetanus booster based on the circumstances of the bite and your vaccination history. Deep bites with tissue damage may require imaging to check for fractures or foreign material like broken tooth fragments.
Most uncomplicated dog bites heal within one to three weeks. Bites requiring surgery for nerve or tendon repair have longer recovery timelines and may need follow-up rehabilitation to restore full function, particularly for hand injuries where fine motor control is involved.