Deflazacort

Pronunciation: de-FLAZ-a-cort.

Generic name
deflazacort
Drug class
Corticosteroid (oxazoline derivative of prednisolone)
Form
Tablet, oral suspension
Route
Oral
Legal status
Prescription-only

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada

Australia: · Full directory

What deflazacort is and how it works

Deflazacort is a prescription-only corticosteroid (glucocorticoid). In the United States it is specifically approved, under the brand name Emflaza, for Duchenne muscular dystrophy (DMD) in patients 2 years of age and older. In the UK and parts of the EU, it is used more broadly for conditions needing glucocorticoid therapy, such as autoimmune disorders, severe allergic reactions, and inflammatory bowel disease. (1) (2)

Your dose of deflazacort is individually worked out by your prescriber based on your weight, condition, and response to treatment -- it is not a fixed dose for everyone. If you have been taking deflazacort for more than a few days, never stop or reduce it on your own; your prescriber will guide you through a gradual, supervised dose reduction if treatment needs to change, because stopping suddenly can be dangerous.

Mechanism of action: how deflazacort works

Deflazacort is an oxazoline-derivative corticosteroid (a prodrug converted to its active metabolite, 21-desacetyldeflazacort) with glucocorticoid receptor agonist activity, providing anti-inflammatory and immunosuppressive effects. 6 mg of deflazacort has approximately the same anti-inflammatory potency as 5 mg of prednisolone. (1) (2)

What deflazacort is used for

Duchenne muscular dystrophy (DMD)

Approved in the United States (as Emflaza) for the treatment of Duchenne muscular dystrophy in patients 2 years of age and older, to help reduce inflammation and preserve muscle strength. (1)

Other conditions requiring glucocorticoid therapy (UK and parts of the EU)

Used more broadly in the UK and some EU countries for autoimmune disorders (such as lupus and rheumatoid arthritis), severe allergic reactions, certain blood cancers, inflammatory bowel disease, and to help suppress the immune system after organ transplantation, as directed by a prescriber. (2)

Before taking deflazacort

Do not take / not appropriate for

  • Do not take deflazacort if you have a known hypersensitivity to deflazacort or any of its ingredients, including previous anaphylaxis with corticosteroid therapy. (all countries) (1) (2)
  • Do not take deflazacort if you have a systemic infection that is not being treated with appropriate anti-infective therapy. (United Kingdom) (2)
  • Do not receive live or live-attenuated vaccines while taking deflazacort; any needed immunisations should be given at least 4-6 weeks before starting treatment, on your prescriber's advice. (all countries) (1) (2)

Tell your clinician about

  • Any history of infections, including tuberculosis, chickenpox, or shingles, and whether you have had chickenpox before.
  • Any history of stomach ulcers, bone density problems (osteoporosis), diabetes, high blood pressure, glaucoma, cataracts, or mental health conditions.
  • All other medicines you take, including anticoagulants, NSAIDs, and any medicines that affect liver enzymes (CYP3A4 inhibitors or inducers).
  • If you are pregnant, planning pregnancy, or breastfeeding.
  • Your child's growth should be monitored regularly by their prescriber during long-term treatment.
(1) (2)

How to take deflazacort

  • Take deflazacort exactly as your prescriber directs, at the dose and schedule individually determined for you.
  • Do not change your dose or stop taking deflazacort on your own, even if you feel well -- any dose changes or discontinuation must be planned and supervised by your prescriber, especially after more than a few days of use, because of the real risk of adrenal insufficiency if stopped abruptly.
  • Keep all appointments for monitoring, including growth checks in children, eye examinations, and bone density assessments as advised by your prescriber.
(1) (2)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6)

Missed dose

Contact your prescriber or pharmacist for specific guidance if a dose is missed, since this can depend on your individual regimen and condition. Do not take an extra dose to make up for a missed one without your prescriber's direction.

Overdose

Seek urgent medical advice if too much deflazacort has been taken. Do not attempt to manage a suspected overdose, or any resulting symptoms, without medical guidance. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Cushingoid appearance (rounded face, changes in body fat distribution).

What to notice: Cushingoid appearance (rounded face, changes in body fat distribution).

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Weight gain and increased appetite.

What to notice: Weight gain and increased appetite.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Upper respiratory infection, cough, and nasopharyngitis (common cold-type symptoms).

What to notice: Upper respiratory infection, cough, and nasopharyngitis (common cold-type symptoms).

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Increased urination frequency.

What to notice: Increased urination frequency.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Unwanted facial or body hair growth, and central (truncal) weight gain.

What to notice: Unwanted facial or body hair growth, and central (truncal) weight gain.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Serious warnings

Signs of adrenal insufficiency or adrenal crisis (especially around dose changes or stopping) — high caution

Symptoms: Severe tiredness, weakness, nausea, vomiting, low blood pressure, or confusion, particularly during illness, injury, or a planned dose reduction.

Action: Never change your dose or stop deflazacort on your own after more than a few days of use. Your prescriber will plan any dose reduction gradually and may advise a temporary dose increase during illness or physical stress. Seek urgent medical attention for any of these symptoms. (1) (2)

Signs of a serious infection — high caution

Symptoms: Fever, chills, worsening cough, or any new or worsening signs of infection; exposure to chickenpox or shingles if you have not had these before.

Action: Contact your prescriber promptly, as corticosteroids can mask signs of infection and increase infection severity. Seek urgent medical evaluation after any chickenpox exposure if you are not immune. (1) (2)

Signs of a serious mood or behavioural change — high caution

Symptoms: Severe depression, unusual mood swings, personality changes, or thoughts of self-harm.

Action: Contact your prescriber promptly, or seek emergency help for thoughts of self-harm. (1) (2)

Vision changes — high caution

Symptoms: Blurred vision, eye pain, or other visual changes, which can indicate cataracts or glaucoma with long-term use.

Action: Tell your prescriber and arrange an eye examination as advised, especially if treatment continues for more than 6 weeks. (1)

Interactions

  • Moderate or strong CYP3A4 inhibitors (certain other medicines) -- your prescriber may reduce your deflazacort dose to about one-third of the usual amount. (1)
  • Strong CYP3A4 inducers -- generally avoided with deflazacort, as they may reduce its effectiveness. (1)
  • Enzyme-inducing medicines such as rifampicin, phenytoin, or carbamazepine -- may require your prescriber to increase your deflazacort maintenance dose. (2)
  • Anticoagulant ('blood-thinning') medicines -- effects can be variably altered; your prescriber will monitor your clotting tests (e.g. INR) more closely. (2)
  • NSAIDs (e.g. ibuprofen) -- increased risk of stomach ulcers when combined with deflazacort. (2)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Deflazacort crosses the placenta. There is no clear evidence of increased birth-defect risk at normal doses, but prolonged use during pregnancy may increase the risk of the baby growing more slowly than expected in the womb. Discuss any pregnancy or plans for pregnancy with your prescriber, who can weigh the benefits and risks for your situation. (1) (2) (3) (4) (5) (6)

Breastfeeding

Deflazacort passes into breast milk. Breastfeeding is generally considered compatible at lower doses (commonly cited as up to about 50 mg/day), but this should be confirmed with your prescriber based on your specific dose and situation. (1) (2) (3) (4) (5) (6)

Children

Approved for Duchenne muscular dystrophy in the US from age 2. Long-term corticosteroid use, including deflazacort, can slow growth and development in children -- regular growth monitoring by a prescriber is important. (1) (2) (3) (4) (5) (6)

Elderly

Older adults may have a higher risk of bone loss (osteoporosis) with corticosteroid use and should be monitored accordingly by their prescriber. (1) (2) (3) (4) (5) (6)

Hepatic_impairment

Liver impairment can increase deflazacort blood levels; your prescriber will use careful monitoring and the lowest effective dose. (1) (2) (3) (4) (5) (6)

Renal_impairment

No specific renal-impairment dosing guidance is established in the sources reviewed for this dossier; discuss any kidney condition with your prescriber. (1) (2) (3) (4) (5) (6)

Monitoring

Before starting

  • Immunisation history and status (live vaccines should be completed at least 4-6 weeks before starting)
  • Baseline growth measurements in children
  • Baseline eye examination and bone density assessment where long-term use is anticipated
  • Screening for existing infections such as tuberculosis where relevant

During treatment

  • Regular growth monitoring in children.
  • Periodic eye examinations, particularly beyond 6 weeks of treatment.
  • Bone density monitoring with chronic use.
  • Blood pressure, blood sugar, and electrolyte checks as directed by your prescriber.
  • Watching for mood or behavioural changes.
(1) (2)

Storage

Store at room temperature, protected from moisture, and out of reach of children, following the specific storage instructions on your product's label (tablets and oral suspension may have different requirements).

Professional information

Clinician-facing context only, sourced from the current US FDA prescribing information and UK SmPC; verify against the current full label before prescribing.

United States

Indication: Duchenne muscular dystrophy

Dose summary: Approximately 0.9 mg/kg/day orally once daily, rounded to available tablet strengths (any combination of the four EMFLAZA tablet strengths may be used); individualised, not fixed. Moderate/strong CYP3A4 inhibitors require dose reduction to about one-third; avoid strong CYP3A4 inducers.

Renal context: Not specifically established in the source reviewed for this dossier. (1)

United Kingdom

Indication: Broad glucocorticoid-responsive conditions

Dose summary: Adults: up to 120 mg/day for acute conditions, maintenance typically 3-18 mg/day. Children: 0.25-1.5 mg/kg/day, sometimes alternate-day. Lowest effective dose should be used. Withdrawal after >3 weeks at doses above ~9 mg/day (physiological-equivalent) must be gradual.

Renal context: Hepatic impairment requires careful monitoring and dose minimisation due to increased blood concentrations; specific renal guidance not detailed in the source reviewed. (2)

Mechanism of action

Hepatic guidance

Hepatic impairment increases deflazacort blood concentrations; use the lowest effective dose with careful monitoring under clinician direction.

Overdose note

Acute overdose is unlikely to be immediately life-threatening, but any suspected overdose should be assessed by a clinician; chronic excessive dosing raises the risk of the corticosteroid-class adverse effects described above. (1) (2)

Frequently asked questions

Is deflazacort available in the US, UK, Europe, Canada, Australia, and New Zealand?

It has standard national approval in the United States (as Emflaza, for Duchenne muscular dystrophy), the United Kingdom (as Calcort), and multiple EU countries (under various national brand names). In Canada and Australia, it is accessed through special/unapproved-medicine supply pathways rather than a standard national marketing authorisation. Its exact approval status in New Zealand could not be independently confirmed in this research and is reported honestly as unresolved. (1) (2) (3) (4) (5) (6)

Can I just stop taking deflazacort if I feel better?

No. If you have taken deflazacort for more than a few days, stopping suddenly can be dangerous because your body's own natural corticosteroid production may be suppressed. Any dose reduction or stopping must be planned and supervised by your prescriber as a gradual taper. (1) (2)

Does deflazacort have a boxed warning?

No, deflazacort does not carry an FDA boxed warning. It does carry standard corticosteroid-class warnings, including adrenal suppression, growth retardation in children with long-term use, increased infection risk, cataracts/glaucoma, cushingoid features, mood/behavioural changes, and bone density loss. (1)

What is the mechanism of action of deflazacort?

Deflazacort is an oxazoline-derivative corticosteroid (a prodrug converted to its active metabolite, 21-desacetyldeflazacort) with glucocorticoid receptor agonist activity, providing anti-inflammatory and immunosuppressive effects. 6 mg of deflazacort has approximately the same anti-inflammatory potency as 5 mg of prednisolone. (1) (2)

What is the generic name of Deflazacort?

The generic name is deflazacort. (1) (2)

What class of drug is deflazacort?

Deflazacort is classed as: Corticosteroid (oxazoline derivative of prednisolone). (1) (2)

References

  1. EMFLAZA (deflazacort) tablets and oral suspension -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information, PTC Therapeutics · United States · accessed 2026-07-30 · source 1
  2. Calcort 6mg Tablets -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- Neon Healthcare Ltd · United Kingdom · accessed 2026-07-30 · source 2
  3. Deflazacort national marketing history and brand names across EU member states (Deflan/Flantadin in Italy since 1985; Deflazacort Alter/Cantabria/Sandoz/Stada, Dezacor, Zamene in Spain since 1990)European national medicines regulators (historical/brand records) -- Italy (AIFA), Spain (AEMPS), and other EU member states · European Union · accessed 2026-07-30 · source 3
  4. Community updates on Deflazacort/Calcort availability in Canada via Health Canada's Special Access ProgramMuscular Dystrophy Canada / Defeat Duchenne Canada community updates, referencing Health Canada's Special Access Program · Canada · accessed 2026-07-30 · source 4
  5. Deflazacort access in Australia via the TGA Special Access Scheme (SAS) Category CTherapeutic Goods Administration (TGA), Australia -- Special Access Scheme · Australia · accessed 2026-07-30 · source 5
  6. Deflazacort funding and access status in New ZealandClinical/patient-advocacy literature referencing New Zealand access pathways (Medsafe Section 29 unapproved-medicine supply framework) · New Zealand · accessed 2026-07-30 · source 6

Brand names by country

Single-ingredient deflazacort names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • KYMBEE18 mg, 22.75 mg/mL, 30 mg, 6 mg, 36 mg · upsher-smith laboratories, llc
  • JAYTHARI30 mg, 6 mg, 18 mg, 22.75 mg/mL, 36 mg · zydus pharmaceuticals (usa) inc.
  • EMFLAZA36 mg, 6 mg, 30 mg, 22.75 mg/mL, 18 mg · ptc therapeutics, inc.
  • PYQUVI22.75 mg/mL · aucta pharmaceuticals, inc.

United Kingdom

  • Calcort (2)MHRA licensed emc smpc confirmed · 6 mg tablet, 30 mg tablet · Neon Healthcare Ltd

Canada

  • Calcort (imported) (4)accessed via health canada special access program not a standard din noc · 6 mg tablet · Supplied under Health Canada's Special Access Program; not a Canadian-approved commercial product
View brands in additional countries.

European Union

Deflan, Flantadin (Italy); Deflazacort Sandoz, Deflazacort Stada, Dezacor, Zamene (Spain) (3)

This page provides general reference information about deflazacort and is not a substitute for advice from the prescriber managing your treatment. All dosing and treatment decisions, including any dose reduction or stopping, should be made with your prescriber.

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