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Heme replacement Pregnancy: §4.6: 'In the absence of specific experimental and clinical data, the risks during pregnancy are not defined; to date, however, no after-effects have been observed in new-born babies whose mothers were treated with NORMOSANG during their pregnancy.' Breast-feeding: not studied; 'since numerous substances are excreted in breast milk, it is appropriate to be cautious when administering NORMOSANG during lactation.' Overall: 'Due to limited data the use of NORMOSANG can not be recommended unless clearly necessary during pregnancy and breast-feeding.'

Haem arginate

Brand names: Normosang

Haem arginate is a haem preparation used to treat acute attacks of hepatic porphyria.

Adult dose

Dose: Acute attack of hepatic porphyria: 3 mg/kg once daily for four days
Route: Intravenous infusion. 'Diluted in 100 ml of 0.9% sodium chloride in a glass bottle and infused intravenously over at least 30 minutes into a large antebrachial or central vein using an inline filter.' After the infusion the vein is rinsed with 100 ml of 0.9% NaCl — 'It is recommended to flush the vein initially with 3 to 4 bolus injections of 10 ml 0.9 % NaCl after which the remaining volume of saline can be infused for 10 - 15 minutes.'
Frequency: Once daily for four days. 'Exceptionally, the course of the treatment may be repeated under strict biochemical surveillance if there is inadequate response after the first course of treatment.'
Max: Maximum 250 mg (1 ampoule) per day — 'The dose should not exceed 250 mg (1 ampoule) per day'
VERBATIM UK SPC §4.2: 'The recommended daily dose is 3 mg/kg once daily for four days, diluted in 100 ml of 0.9% sodium chloride in a glass bottle and infused intravenously over at least 30 minutes into a large antebrachial or central vein using an inline filter. The dose should not exceed 250 mg (1 ampoule) per day. Exceptionally, the course of the treatment may be repeated under strict biochemical surveillance if there is inadequate response after the first course of treatment.' Some sections of the product information we used were incomplete — check the full SPC. Note the 250 mg per-day ceiling binds above roughly 83 kg body weight — at and above that weight the dose is one ampoule, not 3 mg/kg. ELDERLY, VERBATIM: 'No dose adjustment is required.' DILUTION IS MANDATORY: 'As the diluted solution is hypertonic, it should be administered by very slow intravenous infusion only. To prevent vein irritation, the infusion should be administered in at least 30 minutes in a large vein of the forearm or in a central vein.' DIAGNOSIS FIRST, §4.4: 'Before treatment is started, it is necessary to confirm an attack of hepatic porphyria by series of clinical and biological criteria.' 'The sooner NORMOSANG treatment is started after the onset of an attack, the greater its efficacy.'

Paediatric dose

Dose: 3 mg/kg/day
Route: Intravenous infusion, diluted in 100 ml of 0.9% sodium chloride and infused over at least 30 minutes into a large antebrachial or central vein using an inline filter — 'administered with the same precautions as for adults'
Frequency: Once daily for four days
Max: Maximum 250 mg (1 ampoule) per day
Concentration: 25 mg/ml
THIS IS THE LABEL'S OWN PAEDIATRIC FIGURE, NOT A SCALED ADULT DOSE. VERBATIM §4.2 'Children and adolescents': 'Attacks of porphyria are rare in children but limited experience in tyrosinaemia suggests that it is safe to use a dose of not more than 3 mg/kg daily for 4 days, administered with the same precautions as for adults.' The unit is 'mg/kg/day' because the SPC expresses this as a DAILY dose given once daily — with once-daily administration the daily total and the single dose are the same figure. Note the label's wording is a ceiling ('not more than 3 mg/kg daily'), so 3 mg/kg/day is the maximum, not a target to exceed. concentration = 25 because the source product is Normosang 25 mg/ml concentrate — so the volume shown is the volume of CONCENTRATE to withdraw from the ampoule; it must then be diluted in 100 ml of 0.9% sodium chloride in a glass bottle before infusion, and never given undiluted. The 250 mg (one ampoule) daily ceiling applies. Verify any under-18 dose against a children's formulary before administration.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Paediatric weight-based calculator

THIS IS THE LABEL'S OWN PAEDIATRIC FIGURE, NOT A SCALED ADULT DOSE. VERBATIM §4.2 'Children and adolescents': 'Attacks of porphyria are rare in children but limited experience in tyrosinaemia suggests that it is safe to use a dose of not more than 3 mg/kg daily for 4 days, administered with the same precautions as for adults.' The unit is 'mg/kg/day' because the SPC expresses this as a DAILY dose given once daily — with once-daily administration the daily total and the single dose are the same figure. Note the label's wording is a ceiling ('not more than 3 mg/kg daily'), so 3 mg/kg/day is the maximum, not a target to exceed. concentration = 25 because the source product is Normosang 25 mg/ml concentrate — so the volume shown is the volume of CONCENTRATE to withdraw from the ampoule; it must then be diluted in 100 ml of 0.9% sodium chloride in a glass bottle before infusion, and never given undiluted. The 250 mg (one ampoule) daily ceiling applies. Verify any under-18 dose against a children's formulary before administration.

Verify in a children's formulary

Contraindications

  • Hypersensitivity to the active substance or to any of the excipients listed in section 6.1

Side effects

  • Very common: poor venous access
  • Common: infusion site phlebitis, infusion site pain, infusion site swelling
  • Uncommon: serum ferritin increased — 'Increased serum ferritin concentrations have been reported after several years of treatment with repeated infusions, which may indicate an iron overload'
  • Rare: anaphylactoid reaction; hypersensitivity (such as dermatitis medicamentosa and tongue oedema)
  • Rare: pyrexia
  • Not known: headache
  • Not known: injection site thrombosis, venous thrombosis
  • Not known: injection site erythema, injection site pruritus, extravasation, injection site necrosis
  • Not known: skin discoloration
  • Not known: blood creatinine increase
  • §4.4 adds: 'Venous thrombosis in the vein used for infusion may potentially occur following repeated administration of NORMOSANG. There are few cases describing thrombosis at the caval vessels and their major tributaries (iliac and subclavian veins). The risk of thrombosis at the caval vessels cannot be excluded.'

Monitoring

  • Confirm the diagnosis before starting — §4.4: confirm an attack of hepatic porphyria by clinical and biological criteria: 'suggestive family or personal history', 'suggestive clinical signs', and 'quantitative determination of urinary delta-amino-laevulinic acid and porphobilinogen (in preference to the classical WATSON-SCHWARZ or HOESCH tests, which are considered to be less reliable)'
  • §4.4: 'As porphyric attacks are often associated with various cardiovascular and neurological manifestations, appropriate monitoring should be ensured.'
  • Serum ferritin — §4.4: 'Increased serum ferritin concentrations have been reported after repeated infusions. It is therefore recommended that serum ferritin be measured at regular intervals to monitor body iron stores.'
  • Venous access — §4.4: 'Test the cannula before infusing NORMOSANG and also check it regularly during the infusion.' 'If intravenous cannula is in place for too long, due to mechanical irritation and also due to irritation by the injection fluid, vascular damage may occur which may lead to extravasation.' In case of extravasation, skin discoloration may occur
  • §4.4: rinse the vein with 100 ml of 0.9% NaCl after the infusion; peripheral venous alterations after repeated infusions may necessitate a central venous line
  • Expected response — §4.4: 'abdominal pain and other gastro-intestinal symptoms generally disappear within 2 - 4 days. Neurological complications (paralysis and psychological disorders) are less affected by the treatment.'
  • Precipitants — §4.4: warn patients 'of the risk of attacks being worsened or triggered by fasting or taking certain medicinal products (particularly oestrogens, barbiturates and steroids)'
  • Appearance — 'The dark NORMOSANG colour may give the plasma an unusual colouring'
  • ⚠ §4.4 is TRUNCATED in this bundle (it breaks off in the plasma-derived-product infection-prevention paragraph) — this list is not the label's complete set of precautions

Clinical monograph

How it works

It replenishes the regulatory haem pool, suppressing aminolevulinic acid synthase activity and thereby reducing overproduction of porphyrin precursors that drive an acute attack.

Prescribing in practice

  • It must be given by intravenous infusion into a large vein because of the risk of thrombophlebitis and extravasation injury.
  • Treatment should begin early in an acute attack alongside supportive care and removal of precipitating factors.
  • It should be used under specialist guidance for confirmed acute porphyria.

Monitoring

Monitor the infusion site, clinical symptoms of the attack and relevant biochemistry to assess response.

Counselling the patient

  • The infusion is given into a large vein to reduce vein irritation.
  • Avoiding known trigger factors and medicines helps prevent future attacks.
  • Tell clinicians you have porphyria before any new medicine is started.

Evidence & guidelines

Intravenous haem replacement is the established treatment for acute attacks of hepatic porphyria in specialist practice.

Reference: British and Irish Porphyria Network; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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