Cold capping is a technique that cools your scalp before, during, and after chemotherapy to prevent or reduce hair loss. It works by lowering the temperature of your scalp enough to protect hair follicles from the damaging effects of chemo drugs. Success rates range from about 47% to 89% depending on the type of chemotherapy, making it one of the most effective options available for keeping your hair during cancer treatment.
How Scalp Cooling Protects Hair
Chemotherapy drugs target rapidly dividing cells throughout your body, and hair follicle cells are some of the fastest-dividing cells you have. Cold capping works through several mechanisms at once. First, cooling causes blood vessels in the scalp to constrict, reducing blood flow to as little as 20% to 40% of normal levels. Less blood flow means fewer chemo drugs reach the hair follicles in the first place.
But reduced blood flow is only part of the story. At lower temperatures, drug molecules have less energy and move more slowly across cell membranes, so even the drugs that do reach the scalp are less likely to enter hair follicle cells. Cell division itself is an energy-dependent process that slows dramatically in the cold, and since chemo drugs primarily damage cells that are actively dividing, a chilled follicle cell in a resting state is a harder target. The overall metabolic slowdown in cooled cells also reduces the chemical reactions that make certain drugs toxic. All of these effects work together, which is likely why scalp cooling can be so effective.
Manual Caps vs. Automated Systems
There are two main approaches to cold capping, and they differ significantly in how much hands-on effort they require.
Manual cold caps are essentially ice packs shaped to fit your head. They’re stored in dry ice coolers or biomedical freezers before use. Because each cap warms up while you wear it, you need to swap in a fresh one every 20 to 30 minutes throughout your entire infusion. This means you need a helper: a friend, family member, or a trained “capper” you hire to manage the cap changes. You typically rent the caps and bring them to each session in a portable cooler.
Automated scalp cooling systems use a cap connected to a small refrigeration machine controlled by a computer. The machine circulates cooled liquid through the cap continuously, so there’s no need to swap caps during treatment. Three systems are currently sold in the United States: the DigniCap System, the Paxman System, and the Amma Portable Scalp Cooling System by Cooler Heads. The Paxman and Amma systems require a prescription from your doctor before you can sign up.
What a Cold Capping Session Looks Like
Cold capping isn’t something you only wear during the infusion itself. You need to start wearing the cap 30 to 50 minutes before chemotherapy begins, so your scalp is already cooled when the drugs enter your bloodstream. You then wear it throughout the entire infusion.
The post-infusion cooling period is where timing varies the most. Depending on your specific chemo regimen, you may need to keep the cap on for anywhere from 20 minutes to 7 hours after the infusion ends. Some protocols allow patients to continue the post-cooling portion at home rather than staying in the infusion center, which frees up chair space and shortens your time at the clinic. You don’t wear the cap between treatment sessions.
Compliance matters significantly. One study evaluating manual cold caps found a 95% completion rate when patients received detailed instruction and worked with trained cappers, and that high compliance likely contributed to strong outcomes. Getting the cap positioned correctly and wearing it for the full prescribed duration at every session makes a real difference in how well it works.
Success Rates by Chemotherapy Type
Not all chemo drugs respond equally to scalp cooling. In a multicenter study of breast cancer patients, the results broke down clearly by regimen:
- Taxane-based chemotherapy: 89% of patients preserved their hair (49 of 55 patients).
- Sequential anthracycline-taxane regimens: 78% preserved their hair (47 of 60 patients).
- Anthracycline-based chemotherapy: 47% preserved their hair (40 of 85 patients).
The lower success rate with anthracyclines likely reflects the fact that these drugs are particularly damaging to hair follicle cells. Some anthracycline drugs enter cells through active transport mechanisms that cooling can slow but not fully block. If you’re on a taxane-based regimen, your odds of keeping your hair with cold capping are quite good. With anthracyclines alone, it’s closer to a coin flip, though nearly half of patients still benefit.
Side Effects and Safety Concerns
The most immediate side effect is discomfort from the cold itself. Headaches, chills, and scalp pain are common, particularly in the first few minutes of each session. Most patients find the discomfort manageable and tolerable enough to continue, though a small percentage choose to stop.
The bigger question historically has been whether cooling the scalp could allow cancer cells to survive in the scalp area, potentially increasing the risk of scalp metastases. This concern limited adoption in the United States for years. A systematic review and meta-analysis put this fear largely to rest. Among nearly 2,000 patients who used scalp cooling, scalp metastasis occurred in 0.61% of cases. Among over 1,200 patients who did not use scalp cooling, it occurred in 0.41%. That difference was not statistically significant. The incidence of scalp metastasis is extremely low regardless of whether you cool your scalp, and the available evidence does not support the idea that scalp cooling increases the risk.
Cost and Insurance Coverage
In the United States, the total cost of scalp cooling treatment typically runs between $1,500 and $3,000 per patient, depending on how many chemotherapy cycles you need. Manual cold cap systems can cost up to 50% less than automated systems, which makes them a more accessible option, though they require more effort and a helper at each session.
Insurance coverage has been evolving. Medicare has established limited coverage for scalp cooling, with updated billing codes taking effect in early 2026. Private insurance coverage varies widely by provider and plan. Some cancer centers can help you navigate the billing process, and some cold cap companies offer guidance on submitting claims. If cost is a concern, it’s worth asking your treatment center which system they support and what out-of-pocket costs to expect before your first session.
Hair Care During Treatment
Cold capping works best when paired with gentle hair care practices throughout your chemotherapy course. Most protocols recommend avoiding heat styling tools, harsh chemical treatments, and vigorous brushing. The goal is to minimize any additional stress on hair follicles that are already vulnerable from chemo exposure. Your cold cap provider or treatment center will typically give you specific guidelines for washing, drying, and styling your hair during treatment. Following these instructions closely, along with wearing the cap for the full recommended duration at every session, gives you the best chance of preserving your hair.