A TRICHOLOGIST’S GUIDE TO SCIENCE, SUPPORT AND CARE.
Hair follicles produce the strands we commonly call hair. Each follicle works independently and goes through a natural cycle of growth, rest, and renewal.
On a healthy scalp, there are around 80,000 to 150,000 follicles, each at a different stage of this cycle, which is why hair changes are usually gradual rather than sudden.
The hair cycle has 3 primary phases:
Anagen: This is the growth stage and makes up about 90% of a hair’s life. This stage can vary considerably, lasting anywhere from two to seven years.
Catagen: This phase signals the end of the growth stage and typically lasts 10 days.
Telogen: This resting stage occurs when hair remains in the follicle but no longer grows. This phase lasts for 100 days.
Chemotherapy can interrupt the normal hair cycle, particularly during the anagen (growth) phase. This disruption causes a type of hair loss called anagen effluvium.
What Is Anagen Effluvium?
Anagen effluvium is the most common form of chemotherapy-related hair loss. It affects hair in the active growth phase, which accounts for about 85–90% of scalp hair.
Chemotherapy targets rapidly dividing cancer cells, but also affects other fast-growing cells, such as those found in hair follicles. This disrupts hair production, weakening the strands and causing them to break or shed prematurely.
Hair loss often begins within the first week of treatment and can affect large areas of the scalp. The hair sheds before completing its normal cycle, bypassing the usual transition and resting phases.
Although this can be distressing, understanding the process can help you feel more prepared and supported during treatment.
While scalp hair is most visibly affected, other areas such as the eyebrows, eyelashes, and body hair may also be affected, a phenomenon known as universal hair loss. Some people experience full shedding, while others may notice their hair becoming thinner, finer, or structurally weaker.
Hair Regrowth and Recovery
Anagen effluvium is usually temporary. Once the underlying cause, in this case, chemotherapy, is completed and discontinued, hair follicles typically resume activity.
Early regrowth often appears within weeks to months after treatment, though this varies from person to person.
New hair usually grows at a rate of 1.3 cm per month, although individual factors such as genetics, age, and nutrition can influence this. In the early stages, hair may appear softer, finer, or slightly different in texture or colour. These changes are usually temporary, and many people find their hair gradually returns to its usual characteristics over time.
To nurture your scalp and promote healthy hair regrowth during your recovery, we recommend the following hair and scalp care strategies.
Treatment, Support and Care Options
Scalp cooling (cold caps): Worn before, during, and after chemotherapy, cold caps reduce blood flow to the scalp, helping to limit follicle exposure to the drugs. This may reduce hair loss for some, though it’s not suitable for everyone, particularly those with blood cancers.
Scalp health and trichology support: Chemotherapy can also affect scalp health, sometimes leading to dryness, sensitivity, or irritation. A trichologist can assess your scalp condition and recommend a personalised care plan to help manage dryness, sensitivity, or irritation. Supporting scalp health during recovery can help create an optimal environment for healthy hair regrowth.
Wigs and hairpieces: For many, wearing a wig is more than a cosmetic choice; it’s a way to regain confidence and feel more like themselves. High-quality human hair wigs offer a natural look and come in a wide range of textures, colours, and styles.
Hair and scalp care products: If the scalp becomes more sensitive, use hypoallergenic, fragrance-free shampoos, conditioners, and styling products. These should support hydration and effective scalp cleansing without introducing harsh chemicals or allergens.
Avoiding physical and chemical stressors: During and after chemotherapy, it’s advisable to limit heat styling and avoid chemical treatments such as colouring or straightening. These processes can alter disulfide bonds, affecting the hair’s structure, potentially weakening newly growing strands.
Hair loss during chemotherapy can be one of the most visible and difficult aspects of treatment, but for most people, it is temporary. Understanding what is happening within the hair follicle, along with gentle scalp care and appropriate support, can help you feel more informed and confident during this stage. As treatment ends and recovery begins, healthy hair regrowth typically follows.
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