Treat a bad smell from your incision as a reason to call, not something to figure out on your own.
Contact your surgeon if the drainage coming from or around the incision increases or becomes thick, tan, green or yellow, or smells bad. Together, those signs mean pus.
This applies whether your surgical wound is closed or being left open. If you’re doing wet-to-dry dressings, a bad smell from the drainage is also a change to report. Look for drainage that has become darker, thicker or foul smelling.
No smell from an incision is described as harmless. There’s no scale and no set of odor types to go by, and nothing says some smell is expected after surgery. That’s why this article doesn’t reassure you. It’s not because the smell is necessarily serious. It’s because there’s no reassurance to give.
Smell is also rarely the only sign, and noting what comes with it makes your call more useful. Watch for more redness or pain, swelling or bleeding, a wound that is larger or deeper, a wound that looks dried out or dark, and drainage that is increasing or not decreasing after 3 to 5 days.
One practical point about smell: it’s often noticed at a dressing change and then doubted an hour later. If you noticed it, that counts. It doesn’t need to happen again to be worth reporting.