Mohs Surgery: What to Expect Before, During, and After

Hearing "you have skin cancer" is jarring enough. Then comes: "You'll need Mohs surgery." For most patients, this is the moment anxiety spikes — not because the procedure is difficult, but because the unknown is. Here's exactly what the day looks like, from arrival to going home.

Before you arrive: the week before

Stop blood thinners if your surgeon clears it. Ask about stopping aspirin, NSAIDs (ibuprofen, naproxen), fish oil, and vitamin E 5–7 days before surgery. If you take prescription blood thinners (warfarin, clopidogrel, rivaroxaban), do NOT stop these without speaking to your prescribing physician first — we coordinate with them.

Skip skincare on the surgical site the morning of your procedure. No moisturizer, no makeup, no sunscreen directly on the lesion area. A gentle cleanser and that's it.

Eat a normal meal beforehand. Unlike general anesthesia procedures, Mohs is done under local anesthesia — a full stomach is fine and preferred. Bring a snack and water for the waiting periods.

Dress comfortably — button-front or zip-front clothing if the lesion is on your trunk, shoulders, or neck. You may have a dressing in place when you leave.

Bring something to occupy your mind during the processing wait. A companion is also helpful — the day can take 2–4 hours, sometimes more for complex cases.

What happens when you arrive

You'll check in and be brought to a procedure room. The surgeon examines the lesion, marks its visible borders, and takes photographs. Local anesthesia (lidocaine) is injected around the site. This is the most uncomfortable part for most patients: a brief stinging as the numbing takes effect. After 2–3 minutes, the area is completely numb.

The first stage

The surgeon removes a thin, precisely oriented layer of tissue — the first "stage." The wound is temporarily bandaged and you return to the waiting area while the tissue is processed in the on-site lab.

A Mohs surgeon is uniquely both the surgeon and the pathologist on the same day. They embed, section, stain, and review 100% of the deep and lateral margins under the microscope. This takes approximately 45–60 minutes.

Results and additional stages

The surgeon returns with a map of the tissue. If the margins are completely clear, surgery is done — the wound is ready for closure. If any area shows residual cancer cells, the surgeon marks exactly where and removes an additional thin layer in only that precise location — sparing all surrounding healthy tissue.

Most patients require 1–2 stages. The procedure is repeated until the margins are fully clear.

Closure the same day

Once clear margins are confirmed, the defect is assessed and the optimal closure is planned. For most facial wounds, this means primary closure (stitching the edges together). Larger defects may require a small flap, skin graft, or healing by secondary intention.

Closure is done under local anesthesia in the same procedure room. You receive complete written wound care instructions before you leave.

Going home

You go home the same day — most patients are out within 2–4 hours. Mild acetaminophen (Tylenol) is sufficient for pain management for the vast majority of patients. Follow-up is scheduled at 1–2 weeks for suture removal and wound check.

Bottom line

Mohs surgery is a well-orchestrated, methodical procedure. You're awake and can ask questions throughout. Knowing what to expect ahead of time removes most of the fear — and prepares you for the best possible outcome.