Bone Health and Epilepsy – Epilepsy: The Untold Side

Long-term health

People with epilepsy can have a higher risk of reduced bone mineral density and fractures. The reasons are usually mixed: seizures and falls, long-term antiseizure medication, vitamin D deficiency, reduced mobility, menopause, age and other medical risk factors can all contribute.

Key point: bone health is not just a side-effect issue. Fracture risk comes from the interaction between bone strength, falls, seizures, age, mobility, nutrition, hormones and medication. Not everyone with epilepsy needs supplements or a DXA scan, but people with additional risk factors may need assessment.

Why bone health matters in epilepsy

Fractures can cause pain, loss of mobility, hospital admission and reduced independence. People with epilepsy can be exposed to both a greater chance of falling and, in some cases, weaker bones.

Older meta-analysis data found substantially increased fracture risk in epilepsy, with a proportion of fractures directly related to seizures. More recent research continues to support a clinically meaningful association between epilepsy, antiseizure medication and osteoporosis risk.

What is bone mineral density?

Bone mineral density describes how much mineral is present in bone. Lower density can make bones more fragile.

Osteopenia means bone density is lower than expected but not low enough to meet the usual threshold for osteoporosis. Osteoporosis means bones are weakened enough that fracture risk is significantly increased.

Osteomalacia is different from osteoporosis

Osteomalacia is a problem with bone mineralisation, often linked to vitamin D deficiency. NICE specifically warns that long-term treatment with some antiseizure medicines is associated with both reduced bone mineral density and increased risk of osteomalacia.

Which antiseizure medicines are most established in guidance?

NICE names long-term treatment with carbamazepine, phenytoin, primidone and sodium valproate as being associated with decreased bone mineral density and increased risk of osteomalacia.

MHRA safety guidance also highlights phenytoin, carbamazepine, primidone and sodium valproate in relation to lower bone mineral density, and phenobarbital in relation to osteomalacia.

Why enzyme-inducing medicines matter

Some antiseizure medicines induce liver enzymes involved in vitamin D metabolism. This can increase breakdown of vitamin D, which may lead to secondary hyperparathyroidism, increased bone turnover and loss of bone density.

Examples with well-established enzyme-inducing effects include phenytoin, carbamazepine, phenobarbital and primidone.

Not all bone effects are explained by enzyme induction

Sodium valproate is not a classic enzyme inducer yet is still associated with adverse bone effects. Recent reviews also suggest that bone health may be affected through multiple pathways including direct effects on osteoblasts and osteoclasts, sex hormones and mineral metabolism.

What about newer antiseizure medicines?

The evidence is less consistent for newer medicines. A 2025 review suggested that levetiracetam, lacosamide and lamotrigine have a more favourable bone profile than several older or higher-risk medicines, while topiramate and some sodium-channel agents may still affect bone biology.

This does not mean a medicine should be changed solely because of theoretical bone risk. Seizure control, syndrome, side effects, pregnancy considerations, interactions and personal circumstances all matter.

Seizures themselves can increase fracture risk

A fracture can occur because of a fall, impact with furniture or the ground, or powerful muscle contraction during a convulsive seizure.

Even a person with normal bone density can fracture a bone during a severe seizure.

Falls add another layer of risk

Dizziness, imbalance, ataxia, sedation and postictal confusion can increase the likelihood of falling. Ageing, frailty, poor vision, neuropathy and blood-pressure problems can add to this risk.

Bone strength and fall risk should therefore be considered together.

Who may be at higher risk?

Risk can be higher when epilepsy is combined with factors such as:

long-term use of higher-risk antiseizure medicines
multiple antiseizure medicines
previous fragility fracture
frequent falls
postmenopausal status
older age
low body weight
reduced mobility or prolonged immobility
limited sun exposure
low dietary calcium intake
vitamin D deficiency
smoking
high alcohol intake
long-term systemic steroid use
learning disability or physical disability where mobility/nutrition are affected

Vitamin D

Vitamin D is needed for calcium absorption and normal bone mineralisation. Deficiency is common in the general population and can be more likely in some people with epilepsy because of medication, limited mobility, reduced sunlight exposure or other risk factors.

A 2024 review concluded there is not enough evidence to recommend continuous vitamin D supplementation for every person with epilepsy. Monitoring and supplementation should be targeted according to risk.

Calcium

Calcium is an important structural component of bone. Dietary intake should be considered before assuming supplements are needed.

NICE advises considering vitamin D and calcium supplementation for people at risk who are taking antiseizure medicines associated with reduced bone density.

Do not take high-dose supplements automatically

High-dose vitamin D or calcium is not automatically safer. Excessive supplementation can cause harm, including high calcium levels and kidney problems.

Supplementation should follow clinical advice where deficiency or fracture risk is being managed.

Vitamin D testing

There is no single internationally accepted epilepsy-specific screening schedule. Recent epilepsy literature suggests vitamin D measurement is a practical way to identify deficiency in higher-risk people, especially when combined with other bone-health assessment where appropriate.

Testing decisions should reflect medication, age, mobility, diet, sunlight exposure and other osteoporosis risk factors.

What is a DXA scan?

A DXA or DEXA scan is a low-dose X-ray test used to measure bone mineral density. It is commonly used when assessing osteoporosis risk.

Having epilepsy by itself does not mean everyone needs routine DXA scanning.

When might DXA be considered?

In UK practice, fracture risk is usually assessed using the person’s overall risk profile. NICE guidance uses tools such as FRAX or QFracture in appropriate age ranges and advises DXA when the result is likely to affect treatment decisions or when major risk factors are present.

Examples that may prompt bone-density assessment include previous fragility fractures, multiple major risk factors, older age, postmenopausal status or concern about substantial long-term treatment-related risk.

A normal DXA scan does not remove fall risk

A person can still fracture a bone through a seizure-related fall or severe muscle contraction despite normal bone density. DXA assesses bone strength, not seizure severity or environmental risk.

Menopause

Bone density naturally falls more quickly after menopause because of lower oestrogen levels. Long-term antiseizure medication, low vitamin D, low body weight or reduced activity can add further risk.

Menopause is therefore an important point to revisit fracture risk and medication history.

Older age

Older adults may have several risks at once: lower bone density, poorer balance, visual impairment, frailty, polypharmacy and a greater chance of serious injury if they fall.

Children and adolescents

Childhood and adolescence are periods of bone growth and acquisition of peak bone mass. Long-term medication, limited mobility, nutritional problems and developmental disability may therefore have particular importance.

Children should receive age-appropriate vitamin D intake, with extra monitoring or supplementation considered when deficiency risk is higher.

Learning disability and physical disability

People with learning disability or significant physical disability may have higher bone-health risk because of reduced mobility, nutritional difficulties, less sun exposure, long-term medication use and increased fall risk.

Risk assessment should be accessible and individual rather than assuming that bone symptoms will be reported in the usual way.

Weight-bearing activity

Where medically safe, weight-bearing and resistance activity supports bone strength and muscle function. Exercise can also improve balance and reduce falls.

The type of activity should match the person’s seizure pattern, mobility and injury risk rather than applying blanket restrictions.

Diet

A balanced diet containing adequate calcium, protein and vitamin D supports bone health. Dietary sources may reduce the need for supplements in some people.

People on ketogenic dietary therapy need specialist dietetic monitoring because nutrition and bone health require particular attention.

Smoking and alcohol

Smoking and excessive alcohol intake are recognised osteoporosis risk factors. Alcohol can also interact with seizure risk and antiseizure medication.

When fractures deserve further investigation

A fracture after minimal trauma, repeated fractures or vertebral compression fracture may suggest underlying bone fragility and should prompt clinical assessment.

Not every seizure-related fracture indicates osteoporosis, but repeated or unexpectedly severe fractures should not be dismissed as inevitable consequences of epilepsy.

Bone pain and muscle weakness

Osteoporosis is often silent until a fracture occurs. Osteomalacia, however, can sometimes cause diffuse bone pain or muscle weakness.

Persistent symptoms need assessment because many other conditions can cause similar problems.

Medication review should be balanced

If bone risk is high, clinicians may review whether the current antiseizure medicine remains the best choice. This does not mean abruptly stopping or switching an effective medicine.

Any change must balance seizure control against bone risk and the person’s other treatment needs.

What to discuss at a review

Useful questions include:

Which antiseizure medicines have I taken and for how long?
Do I have additional osteoporosis risk factors?
Have I had a fragility fracture?
Do I fall frequently?
Is my vitamin D status worth checking?
Is my dietary calcium intake adequate?
Would formal fracture-risk assessment help?
Would a DXA scan change management?

The central point

Bone health in epilepsy is about more than one medicine and more than one test.

The best approach is to identify the person’s combined fracture risks, reduce avoidable falls, review long-term medication exposure, correct nutritional deficiencies where present and use fracture-risk assessment or DXA when clinically appropriate.

Where next?

Medication Side Effects and Interactions →
Injuries After Seizures →
Epilepsy Across the Lifespan →
Epilepsy in Older Adults →
Back to Understanding Epilepsy →

Sources

Medical note: This page is educational. Do not stop or change antiseizure medication because of bone-health concerns without medical advice. Vitamin D, calcium, fracture-risk assessment and DXA scanning should be individualised according to risk.

Evidence checked: September 2026.