Hair Loss and Colon Cancer Treatment: How Common Is It and How To Manage It

Hair loss can happen with some colon and rectal cancer treatments, but it’s not universal and often depends on the specific medications used. Chemotherapy can damage fast‑dividing hair follicle cells, so certain regimens may cause thinning or hair loss, while others may not. ^[1] Targeted therapies generally do not cause hair loss and tend to have fewer “chemo‑like” side effects. ^{[2] [3]}

How common is hair loss with colon cancer treatment?

• Chemotherapy: Hair loss is a known side effect of some, but not all, chemotherapy drugs used for colorectal cancer because they affect rapidly dividing cells (including hair follicles). ^[1] Institutions may offer scalp cooling (cold caps) during infusion to reduce hair loss risk. ^[4]
• Targeted therapy: These drugs focus on specific cancer cell signals and typically do not cause hair loss; they are less likely to cause low blood counts compared to standard chemo. ^{[2] [3]}
• Radiation: Radiation affects hair only in the area being treated; if the scalp isn’t in the radiation field, hair loss on the head is unlikely. ^[5]

Which drugs are more likely to cause hair loss?

• Intravenous 5‑FU (fluorouracil)–based regimens and combinations (e.g., FOLFIRI with irinotecan) can cause hair thinning or loss; irinotecan labeling lists alopecia among possible adverse events. ^[6] Regimen‑specific risk varies, and not everyone loses hair with these treatments. ^[1]
• Capecitabine (oral 5‑FU prodrug) tends to have lower rates of alopecia compared with IV 5‑FU, though hand‑foot syndrome and gastrointestinal side effects may be more prominent. [PM13]
• Targeted agents (EGFR, VEGF, BRAF, HER2, NTRK, RET inhibitors): hair loss is generally uncommon with these treatments. ^{[2] [3]}

When does hair loss start and does it grow back?

• Timing: If hair loss occurs, it usually starts within the first few weeks of chemotherapy. ^[5]
• Regrowth: Hair typically grows back after treatment ends, though texture or color may change temporarily. ^[7]

Practical ways to prevent or reduce hair loss

• Scalp cooling (cold caps): Wearing a cooled cap before, during, and after chemo can reduce blood flow to hair follicles and lower drug uptake, helping preserve hair; success varies by regimen. ^{[4] [8]} Many centers provide structured scalp‑cooling programs and guidance. ^[9]
• Gentle hair care: Use mild shampoos, avoid harsh chemicals and heat styling, brush gently, and pat dry to minimize breakage. ^[9]
• Nutrition and hydration: A balanced diet with lean protein, whole grains, fruits, and vegetables supports overall hair health during treatment. ^[10]

Coping strategies if hair loss happens

• Wigs and hairpieces: Consider getting fitted before significant hair loss to match color and style; many insurance plans cover medical wigs with a prescription. ^{[11] [12]}
• Head coverings: Scarves, turbans, and hats provide comfort and style options; choose materials and fits that feel secure and breathable. ^[13]
• Styling tips: Cutting hair shorter before treatment can make thinning less noticeable and easier to manage; products that camouflage thinning areas may help. ^[9]
• Emotional support: Lean on friends, family, and support groups; this change is usually temporary, and resources can make the transition easier. ^[7]

Other common side effects to be aware of

Alongside hair changes, chemotherapy may cause fatigue, nausea, vomiting, appetite loss, neuropathy, and low blood counts, which your care team can help manage with medications and supportive care. ^[4]

Key takeaways

• Hair loss is possible with some colorectal cancer chemotherapies, especially those that impact fast‑dividing cells, but it is not guaranteed. ^[1]
• Targeted therapies usually do not cause hair loss. ^{[2] [3]}
• Scalp cooling, gentle hair care, and early wig/covering planning can make a meaningful difference in comfort and confidence during treatment. ^{[4] [9] [12] [11] [13]}
• Most hair loss, when it happens, is temporary and hair tends to regrow after therapy. ^[7]