Hair loss

Hair loss, also called alopecia, means losing more hair than expected or noticing visible changes in hair density, hairline shape, or bald areas on the scalp or other hair-bearing parts of the body. It can develop slowly over years, appear suddenly after stress or illness, or show up as round patches, diffuse shedding, widening of the part line, or thinning around the temples and crown.

Many people first notice hair loss during everyday routines: more hair in the shower drain, extra shedding while brushing, a thinner ponytail, more visible scalp under bright light, or a hairline that looks different in photos. Hair loss is not always permanent, but the pattern, speed, scalp appearance, and associated symptoms matter when deciding whether medical evaluation is needed.

How hair loss can feel and appear

Hair loss does not look the same for everyone. Some people lose hair evenly across the scalp, while others notice localized bald spots or gradual thinning in a typical pattern. In men, hereditary hair loss often starts with a receding hairline or thinning at the crown. In women, it often appears as widening of the central part or reduced density over the top of the scalp.

Hair loss can also involve the beard, eyebrows, eyelashes, or body hair. Some forms are painless and mainly cosmetic, while others come with itching, burning, scaling, tenderness, redness, or small bumps around hair follicles. These scalp symptoms are clinically important because they may point toward inflammation, infection, or scarring hair loss, where earlier evaluation can matter.

Common causes of hair loss

Hereditary and hormonal causes

One of the most common patterns is androgenetic alopecia, often called male or female pattern hair loss. It is linked to genetic sensitivity of hair follicles and hormonal influence. The hair gradually becomes thinner and shorter over time. This type usually progresses slowly and may be more noticeable with age, although it can begin earlier in adulthood.

Hormonal changes can also contribute to increased shedding or thinning. Hair loss may appear after pregnancy, during menopause, with thyroid imbalance, or in conditions that affect androgen levels. In these cases, the pattern and medical history help guide which tests or treatment options may be useful.

Stress, illness, medication, and nutritional factors

Diffuse shedding can happen after fever, surgery, major emotional stress, rapid weight loss, severe infection, or a significant change in general health. This is often related to telogen effluvium, where many hairs enter the shedding phase at the same time. The shedding may start weeks or months after the trigger, which can make the cause less obvious.

Certain medications, nutritional deficiencies, low iron stores, restrictive diets, and some chronic diseases can also affect hair growth. Hair is sensitive to the body’s overall metabolic state, so unexplained shedding sometimes leads to blood tests, medication review, and assessment of recent health changes.

Inflammatory, autoimmune, infectious, and traction-related causes

Alopecia areata is an autoimmune condition that can cause round or oval patches of hair loss. Fungal infections of the scalp, inflammatory scalp diseases, and some scarring alopecias can also lead to visible hair loss. Hairstyles that pull tightly on the hair, extensions, chemical damage, or repeated heat styling may contribute to traction-related thinning or breakage.

Symptoms that may appear with hair loss

Associated symptoms can help narrow the possible cause. A dermatologist or other specialist will often ask whether the hair loss is sudden or gradual, patchy or diffuse, painful or painless, and whether the scalp itself looks normal.

• Increased daily shedding when washing, brushing, or touching the hair
• Visible thinning over the crown, temples, or part line
• Round or irregular bald patches
• Itching, burning, tenderness, scaling, redness, or crusting on the scalp
• Hair breakage rather than full hair shedding from the root
• Loss of eyebrow, beard, eyelash, or body hair
• Nail changes, fatigue, weight change, menstrual changes, or other systemic symptoms

When hair loss needs medical attention

Hair loss is not always urgent, but some patterns should be assessed without unnecessary delay. Medical evaluation is especially useful when hair loss is sudden, patchy, rapidly worsening, associated with scalp inflammation, or affecting emotional wellbeing.

• Sudden hair loss over a short period
• Patchy bald areas, especially if they are expanding
• Scalp pain, burning, redness, swelling, scaling, pus, or crusting
• Hair loss with scarring, shiny skin, or loss of follicle openings
• Hair loss after starting a new medication or after major illness
• Hair loss with fatigue, unexplained weight change, heavy periods, or hormonal symptoms
• Hair loss in children

Early assessment is particularly important when scarring alopecia, infection, or significant inflammation is possible because these conditions may damage follicles if left untreated.

How hair loss is usually diagnosed

Clinical history and scalp examination

Diagnosis usually starts with a careful discussion about the pattern, duration, triggers, family history, medical conditions, medications, diet, hair-care habits, pregnancy history, and stress or illness in the previous months. The scalp is examined for density, distribution, redness, scaling, scarring, broken hairs, and follicle changes.

A clinician may gently pull a small group of hairs, examine the hair shafts, or use magnification to assess the scalp and follicles. Photographs may help track progression over time, especially when hair loss is gradual.

Tests that may be used

Depending on the pattern, tests may include blood work for iron status, thyroid function, vitamin or nutritional markers, hormone-related concerns, inflammation, or autoimmune clues. If infection is suspected, a scalp sample may be taken. In unclear cases or suspected scarring alopecia, a small scalp biopsy may be recommended.

Treatment options that may help

Treatment depends on the cause. For hereditary hair loss, topical or oral medications may be considered when medically appropriate. For shedding related to illness, stress, medication, deficiency, or hormones, the main approach is to identify and address the trigger. Inflammatory or autoimmune hair loss may require targeted dermatologic treatment. Infection-related hair loss needs appropriate antimicrobial therapy.

Some patients also explore regenerative or restorative options, depending on the diagnosis, follicle status, stage of hair loss, and medical suitability. These may include scalp-focused regenerative treatments or hair restoration planning, but they should be discussed only after a clear diagnosis because not every type of hair loss responds to the same approach.

Through ZagrebMed, patients can send an inquiry for guidance toward an appropriate specialist evaluation, especially when hair loss is persistent, distressing, unexplained, or connected with scalp symptoms.

What to prepare before a medical appointment

Before a consultation, it helps to prepare a short timeline: when the hair loss started, whether it is getting worse, what pattern you notice, and whether there was illness, stress, pregnancy, weight loss, medication change, or a new hair-care routine in the months before shedding began. Bring a list of medications and supplements, recent blood tests if available, and photos showing earlier hair density if they help show the change.

Also note scalp symptoms such as itching, pain, scaling, redness, or tenderness. These details help the clinician decide whether the problem is likely to be hereditary, inflammatory, autoimmune, infectious, hormonal, nutritional, medication-related, or triggered by a recent event.