Acromegaly vs Gigantism: Age and Growth Differences

Acromegaly and gigantism are caused by too much growth hormone, most often from a noncancerous pituitary gland tumor. Gigantism begins before the growth plates close and mainly causes unusual height gain, while acromegaly begins after growth is complete and causes enlargement of the hands, feet, face, and internal tissues.

Acromegaly vs Gigantism at a Glance

Acromegaly and gigantism are two forms of growth hormone excess. They are closely related, but doctors use different names because excess growth hormone has different effects before and after the long-bone growth plates, also called epiphyseal plates, have closed.

Feature	Gigantism	Acromegaly
Usual age when hormone excess begins	Childhood or adolescence, before growth plates close	Adulthood, after growth plates close
Most noticeable growth change	Very rapid linear growth and unusual height for age	Enlargement of hands, feet, jaw, nose, and soft tissues rather than increased height
Common underlying cause	Usually a growth hormone-secreting pituitary adenoma	Usually a growth hormone-secreting pituitary adenoma
Other possible effects	Headaches, vision changes, delayed puberty, enlarged hands and feet	Headaches, sweating, joint pain, sleep apnea, high Systolic Blood Pressure: What Patients Need to Know" class="ahp-ilk">blood pressure, and changes in glucose control
Relationship between the conditions	May continue into adulthood and produce features of acromegaly	Does not cause increased adult height

In both conditions, the body is exposed to too much growth hormone over time. This increases production of insulin-like growth factor 1, or IGF-1, a hormone made mainly by the liver that carries many of growth hormone’s effects to tissues throughout the body.

How the Changes Look and Feel

Gigantism is often first recognized when a child or teenager grows much faster than expected for their family pattern and age. They may become noticeably taller than peers over a relatively short period. Their hands and feet may also enlarge, and some young people develop headaches, excessive sweating, tiredness, or changes in vision.

Acromegaly usually develops gradually, sometimes over years. A person may realize that rings no longer fit, shoe or glove size has increased, or facial features appear broader or more prominent in photographs. The jaw may become more prominent, spaces may develop between teeth, and the tongue can enlarge. These changes are not caused by ordinary weight gain or aging alone.

Growth hormone excess can affect more than outward appearance. Either condition may be associated with joint and muscle discomfort, carpal tunnel symptoms, oily skin, increased sweating, fatigue, snoring or obstructive sleep apnea, and changes in blood sugar. Some people have menstrual irregularities, reduced fertility, erectile difficulties, or reduced sexual desire because a pituitary tumor can affect other hormone systems.

Why They Happen and Who May Be Affected

The most common cause of acromegaly or gigantism is a pituitary adenoma. This is a usually benign, or noncancerous, growth in the pituitary gland, a pea-sized gland at the base of the brain. The tumor may release excess growth hormone and can sometimes press on nearby structures as it enlarges.

In rare situations, excess growth hormone is linked to a tumor elsewhere in the body that produces growth hormone-releasing hormone. Some cases, particularly those beginning at a young age or occurring in more than one family member, can be associated with inherited genetic conditions. A clinician may consider genetic evaluation when the age of onset, family history, or other findings suggest this possibility.

These disorders are not caused by a child eating too much, exercising too little, or an adult gaining weight. Because the physical changes may be slow and subtle, people can overlook symptoms for a long time. Recognizing the pattern and obtaining appropriate testing are important steps toward effective care.

How a Clinician Tells Them Apart

Doctors first determine when the excessive growth began. In a child, they review height measurements over time using standardized growth charts, assess the pace of growth, and consider pubertal development. A child with gigantism often has growth that crosses upward through expected height percentiles and does not match their usual family growth pattern.

For an adult, the clinical history focuses on progressive changes in shoe, ring, hat, or glove size; facial changes; headaches; sweating; and symptoms affecting sleep, joints, vision, or metabolism. Comparing older photographs can occasionally help show gradual changes. A physical examination also looks for enlarged hands and feet, jaw changes, skin changes, and signs of other pituitary hormone problems.

The main screening blood test is an age-adjusted IGF-1 level. If it is elevated, clinicians usually perform further growth hormone testing, often measuring whether growth hormone suppresses appropriately after a glucose drink. Results must be interpreted carefully because age, puberty, pregnancy, diabetes, liver or kidney disease, nutrition, and some medicines can influence testing.

If laboratory findings support growth hormone excess, magnetic resonance imaging (MRI) of the pituitary gland is typically used to look for an adenoma. Visual field testing may be needed if the tumor is near the optic nerves, and additional blood tests assess other pituitary hormones and related health concerns.

What Happens After Diagnosis

Care is individualized and usually involves an endocrinologist, a pituitary surgeon, and other specialists as needed. The main goals are to normalize growth hormone and IGF-1 levels, remove or control the tumor, preserve normal pituitary function, and address complications such as sleep apnea, high blood pressure, diabetes, or joint problems.

For many people with a removable pituitary adenoma, surgery through the nose and sphenoid sinus, called transsphenoidal surgery, is the preferred initial treatment. Whether surgery is suitable depends on the tumor’s size, location, spread, and the person’s overall health. Experienced pituitary teams can explain the potential benefits, limitations, and follow-up testing involved.

Medicines may be used when surgery is not possible, does not fully control hormone levels, or while further treatment is being planned. Options can include somatostatin receptor ligands, a growth hormone receptor blocker, or selected dopamine agonists. Radiation therapy may be considered for persistent disease, but its hormone-lowering effect is gradual and requires long-term monitoring.

A child with gigantism needs care from a pediatric endocrinology team familiar with growth and puberty. Treatment still targets the source of hormone excess, but planning also considers developing bones, pubertal timing, emotional wellbeing, schooling, and long-term follow-up. If gigantism began before growth plates closed, some acromegaly features may remain or develop after adulthood unless hormone excess is controlled.

Monitoring Health and Supporting Daily Life

Even after successful treatment, regular follow-up is important. Clinicians monitor IGF-1 and, when appropriate, growth hormone levels, repeat imaging when indicated, and assess whether the pituitary gland is making adequate amounts of other hormones. Some people require hormone replacement if pituitary function is reduced by the tumor or its treatment.

Doctors may also screen for conditions linked with prolonged growth hormone excess. Depending on the individual, this can include evaluation for high blood pressure, changes in blood glucose, heart enlargement or rhythm concerns, sleep apnea, arthritis, and colon polyps. Screening recommendations should be tailored to age, symptoms, medical history, and local clinical guidance.

There is no home remedy that can correct a pituitary tumor or reliably lower excess growth hormone. However, keeping follow-up appointments, taking prescribed treatment as directed, using support for sleep or joint symptoms, and discussing emotional concerns can make a meaningful difference. Family support and age-appropriate counseling can be particularly valuable for children and adolescents coping with visible changes.

When to Seek Medical Care

A parent or caregiver should arrange a medical assessment if a child is growing unusually rapidly, is much taller than expected for their growth pattern, or has new headaches, vision changes, enlarged hands or feet, or unexpected changes in puberty. Rapid growth has several possible causes, and early assessment helps identify the right explanation.

Adults should speak with a doctor if they notice progressive enlargement of the hands, feet, jaw, or facial features; increasing ring or shoe size; persistent headaches; excessive sweating; snoring with daytime sleepiness; or unexplained changes in blood pressure or blood sugar. These symptoms are common in other conditions as well, but their combination deserves review.

Urgent medical evaluation is appropriate for sudden severe headache, sudden loss or marked change of vision, confusion, fainting, or vomiting accompanied by severe headache. These symptoms are uncommon but may signal a problem requiring prompt assessment. Acıbadem Health Point’s multidisciplinary specialists and JCI-accredited hospitals evaluate and treat pituitary conditions for international patients.

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