Do not take an antibiotic just because the cut came from a rusty wire. Rust itself does not cause tetanus, and antibiotics do not prevent tetanus. A puncture or dirty cut needs thorough cleaning and a check of your tetanus vaccination status. The CDC wound guidance specifically advises against antibiotics for tetanus prevention.

When antibiotics may be used: only if a clinician thinks there is a bacterial wound infection or the wound is high risk, such as a deep contaminated puncture, delayed treatment, retained foreign material, bite, diabetes, poor circulation, or immune suppression. The choice depends on the wound, allergies, and local resistance, so it should not be self-started.

Seek urgent care today if it is a deep puncture, there may be wire left inside, it is on the foot or near a joint, or your tetanus status is uncertain. Seek care promptly for spreading redness, warmth, swelling, pus, fever, red streaks, worsening pain, numbness, trouble moving the area, jaw stiffness, or muscle spasms.

No antibiotic should be started “stat” solely for a rusty-wire cut. It will not prevent tetanus, and routine antibiotics are not advised for an uncomplicated puncture wound. The priority is cleaning, checking for a retained wire fragment, and tetanus prevention.

Go to urgent care today if the cut is deep, dirty, on the foot/hand, happened through footwear, is more than a few hours old, or you have diabetes, poor circulation, or reduced immunity. A clinician may prescribe an antibiotic only if the wound is high risk or shows infection, and the right drug depends on the site, depth, contamination, allergies, and whether a foreign body remains.

Get a Tdap/Td booster today if it was a dirty/puncture wound and your last tetanus dose was 5 or more years ago, or you are unsure. If you have had fewer than 3 lifetime tetanus vaccine doses or do not know your history, you may need TIG plus vaccination. This is consistent with CDC tetanus wound guidance.

Seek emergency care for fever, spreading redness, pus, severe or increasing pain, red streaks, numbness, trouble moving the limb, jaw stiffness, or muscle spasms.