Posaconazole Amarox
Broad-spectrum triazole antifungal for prevention and treatment of invasive fungal infections
Quick facts about Posaconazole Amarox
Key takeaways about Posaconazole Amarox
- Broad-spectrum antifungal activity: Posaconazole covers yeasts (Candida, Cryptococcus), moulds (Aspergillus, Fusarium) and the Mucorales fungi responsible for mucormycosis – a spectrum wider than fluconazole or itraconazole
- Intravenous formulation for hospital use: Each 16.7 mL vial delivers 300 mg of posaconazole, diluted before infusion and administered over approximately 90 minutes through a central venous catheter
- Loading dose on day 1: Standard adult dosing is 300 mg twice on day 1, followed by 300 mg once daily; patients are switched to oral posaconazole as soon as clinically feasible
- Major drug interactions via CYP3A4: Posaconazole strongly inhibits CYP3A4 and can dangerously raise blood levels of sirolimus, tacrolimus, vinca alkaloids, certain statins, midazolam and venetoclax; some combinations are strictly contraindicated
- Renal caution with IV formulation: The cyclodextrin excipient (betadex sulfobutyl ether sodium) can accumulate in moderate to severe renal impairment; oral posaconazole is preferred in these patients whenever possible
What Is Posaconazole Amarox and What Is It Used For?
Posaconazole Amarox is an intravenous, broad-spectrum triazole antifungal used in adults to prevent invasive fungal infections in severely immunocompromised patients and to treat invasive aspergillosis, fusariosis, chromoblastomycosis, mycetoma, coccidioidomycosis and refractory oropharyngeal candidiasis. It contains the active substance posaconazole and is reserved for hospital use under specialist supervision.
Posaconazole Amarox belongs to the triazole class of antifungal medicines, the same family as fluconazole, itraconazole, voriconazole and isavuconazole. It is classified as a second-generation triazole, meaning it was designed to overcome some of the limitations of first-generation azoles by extending the antifungal spectrum to include moulds such as Aspergillus and the Mucorales fungi (Rhizopus, Mucor and related species). This broader reach is clinically critical, because moulds and mucormycetes are among the most common and most lethal causes of invasive fungal disease in patients with neutropenia or after allogeneic stem cell transplantation.
The active ingredient, posaconazole, works by inhibiting a fungal enzyme called lanosterol 14-alpha-demethylase (CYP51). This enzyme is required for the synthesis of ergosterol, the main sterol of the fungal cell membrane. When ergosterol production is blocked, toxic methylated sterol precursors accumulate, the membrane loses its integrity, and the fungus can no longer grow or divide. In most species the net effect is fungistatic (inhibitory), but against some moulds – particularly Aspergillus species and Mucorales – posaconazole exerts fungicidal activity at clinically achievable concentrations.
The intravenous concentrate contains 300 mg of posaconazole dissolved in 16.7 mL (18 mg/mL) with the solubiliser betadex sulfobutyl ether sodium. Compared with older oral suspension formulations of posaconazole, the intravenous route bypasses the highly variable gastrointestinal absorption seen in sick, fasting or vomiting patients, and delivers more predictable and consistent plasma exposure. This is particularly important in critically ill patients where rapidly achieving therapeutic drug levels can mean the difference between survival and fatal progression of a fungal infection.
Approved indications in adults
Posaconazole Amarox is licensed in the European Union, United Kingdom, United States and many other jurisdictions for the following indications, typically when oral therapy is not feasible or during the first days of severe infection before switching to tablets or suspension:
- Invasive aspergillosis in patients whose disease is refractory to amphotericin B or itraconazole, or who cannot tolerate these medicines
- Fusariosis in patients with disease refractory to amphotericin B, or in patients who are intolerant of amphotericin B
- Chromoblastomycosis and mycetoma in patients whose disease has failed to respond to itraconazole, or who are intolerant of itraconazole
- Coccidioidomycosis in patients with disease refractory to amphotericin B, itraconazole or fluconazole, or in patients who are intolerant of those medicines
- Oropharyngeal candidiasis as first-line therapy in patients with severe disease or in whom response to topical treatment is expected to be poor
- Prophylaxis of invasive fungal infections in high-risk groups:
- Patients receiving remission-induction chemotherapy for acute myeloid leukaemia (AML) or myelodysplastic syndromes (MDS) who are expected to experience prolonged neutropenia
- Haematopoietic stem cell transplant (HSCT) recipients receiving high-dose immunosuppressive therapy for graft-versus-host disease (GvHD) who are at high risk of developing invasive fungal infections
Mucormycosis: an emerging off-label role
Although not historically listed in the EMA or FDA label, posaconazole has become a cornerstone of salvage and step-down therapy for mucormycosis (the infection caused by Mucorales fungi such as Rhizopus, Mucor, Lichtheimia and Cunninghamella). International guidelines from the ECMM (European Confederation of Medical Mycology), ISHAM and ASM consider posaconazole a reasonable alternative or step-down option after initial induction with liposomal amphotericin B, particularly after clinical stabilisation. Mucormycosis gained worldwide attention during the COVID-19 pandemic when a large number of cases were reported in patients with diabetes and those who had received corticosteroids.
Use in children and adolescents
The intravenous concentrate is approved in several jurisdictions for use in adolescents aged 13 years and over, at the same dose as in adults. Use in children under 13 years is not generally recommended with this specific formulation because of insufficient safety and pharmacokinetic data; alternative antifungal agents or age-appropriate oral posaconazole formulations may be considered by a paediatric infectious disease specialist.
The introduction of posaconazole prophylaxis has been one of the most important advances in supportive haemato-oncology care in the last two decades. Landmark trials (Cornely et al., NEJM 2007; Ullmann et al., NEJM 2007) showed that posaconazole prophylaxis significantly reduced invasive fungal infections and overall mortality compared with fluconazole or itraconazole in patients with prolonged neutropenia or severe graft-versus-host disease. These findings underpin current ECIL and IDSA recommendations.
What Should You Know Before Taking Posaconazole Amarox?
Before Posaconazole Amarox is given, your clinical team must review your full medication list, heart rhythm (ECG), electrolyte levels (potassium, magnesium, calcium), and liver and kidney function. Tell them about any allergy to azole antifungals, any history of liver disease, heart rhythm problems, or QT prolongation, as well as pregnancy or breastfeeding. The intravenous formulation should generally be avoided in patients with moderate to severe kidney impairment.
Because Posaconazole Amarox is used in patients who are often critically ill and already receiving many other medicines, careful clinical assessment before every infusion is essential. Your hospital team will typically check blood tests, review drug charts, obtain a baseline ECG and ensure that a central venous catheter is correctly positioned before starting therapy.
Contraindications
Posaconazole Amarox must not be given in the following situations:
- Hypersensitivity to posaconazole or to any of the excipients (including betadex sulfobutyl ether sodium), or a documented severe allergic reaction to any other azole antifungal
- Co-administration with the ergot alkaloids ergotamine or dihydroergotamine, because posaconazole can raise their levels and precipitate ergotism (severe vasoconstriction, ischaemic limb damage)
- Co-administration with the CYP3A4 substrates terfenadine, astemizole, cisapride, pimozide, halofantrine or quinidine, because of the risk of QT prolongation and potentially fatal ventricular arrhythmia (torsades de pointes)
- Co-administration with HMG-CoA reductase inhibitors primarily metabolised by CYP3A4, specifically simvastatin, lovastatin and atorvastatin, because of the risk of rhabdomyolysis
- Co-administration with venetoclax during the dose-titration (ramp-up) phase in patients with chronic lymphocytic leukaemia, where very high venetoclax levels can trigger life-threatening tumour lysis syndrome
- Co-administration with naloxegol (peripherally acting opioid antagonist) and with the long-acting sedative sirolimus
The above combinations are absolutely contraindicated because they may cause fatal cardiac arrhythmias, rhabdomyolysis, ergotism or tumour-lysis syndrome. Share your full medicine list – including any over-the-counter products, herbal supplements and recreational drugs – with your doctor and pharmacist before the first dose.
Warnings and precautions
Extra caution is required in the following situations. Your clinical team will weigh the benefits of posaconazole therapy against the risks and, if needed, monitor you more closely:
- Heart rhythm disorders: Posaconazole can prolong the QT interval on the ECG. Baseline and in-treatment ECG monitoring is recommended in patients with congenital or acquired long-QT syndrome, structural heart disease, bradycardia, previous symptomatic arrhythmias or those taking other QT-prolonging drugs
- Electrolyte disturbances: Low potassium, magnesium or calcium levels increase the risk of QT prolongation; these should be corrected before starting and monitored during treatment
- Liver disease: Elevated liver enzymes, cholestasis, hepatitis and, rarely, severe liver failure (including fatal cases) have been reported. Patients with pre-existing liver disease need careful monitoring. Liver function tests should be performed at baseline, during treatment and at any sign of hepatic dysfunction
- Renal impairment: The IV formulation contains the excipient betadex sulfobutyl ether sodium, which accumulates in patients with moderate to severe renal impairment (eGFR <50 mL/min/1.73 m²). Unless the expected benefit outweighs the risk, the oral formulation is preferred. If the IV formulation must be used, serum creatinine should be monitored closely and a switch to oral therapy considered as soon as clinically feasible
- Infusion reactions: Hypersensitivity and infusion-related reactions (flushing, chest discomfort, dyspnoea, rigours) have been reported. The infusion should be stopped if any reaction occurs and appropriate supportive measures started
- Vinca alkaloid toxicity: Co-administration with vincristine or vinblastine markedly increases the risk of severe or fatal neurotoxicity (ileus, seizures, polyneuropathy, SIADH). These combinations should be avoided whenever possible
- Pseudoaldosteronism: High-dose posaconazole can inhibit 11β-hydroxysteroid dehydrogenase type 2, leading to hypokalaemia, hypertension and fluid retention in rare cases
Pregnancy and breastfeeding
There are no adequate and well-controlled studies of posaconazole in pregnant women. Animal studies have shown reproductive toxicity, including skeletal malformations and increased embryo-foetal loss at doses comparable to human therapeutic exposure. Posaconazole Amarox should therefore not be used during pregnancy unless the potential clinical benefit to the mother clearly outweighs the potential risk to the foetus. Women of childbearing potential must use effective contraception during treatment. If a patient becomes pregnant while receiving posaconazole, she should be counselled on the potential risks and referred for specialist obstetric review.
Breastfeeding: Posaconazole is excreted in the milk of lactating rats. It is not known whether it passes into human milk, but because of the potential for serious adverse reactions in a breastfed infant, breastfeeding should be discontinued when the mother is receiving Posaconazole Amarox.
Use in older adults
No dose adjustment is required based on age alone. However, older adults may have decreased renal function, reduced hepatic reserve and more comorbidities, so special attention should be given to electrolytes, QT interval, drug interactions and renal function during therapy.
Effects on driving and using machines
Because Posaconazole Amarox is administered in hospital to patients who are typically unwell, driving is not usually a practical concern during the IV course. However, if a patient resumes driving after discharge on an oral posaconazole formulation, they should be aware that dizziness, somnolence or blurred vision have been reported and should avoid driving or operating machinery if these occur.
How Does Posaconazole Amarox Interact with Other Drugs?
Posaconazole is a potent inhibitor of the CYP3A4 enzyme and of the P-glycoprotein transporter. It can dramatically raise blood levels of many co-administered medicines, including immunosuppressants (sirolimus, tacrolimus, ciclosporin), chemotherapy (vincristine, vinblastine, venetoclax), certain statins, benzodiazepines (midazolam), and some anticoagulants. Some combinations are absolutely contraindicated; many others require dose reduction or drug-level monitoring.
Drug interactions are among the most important clinical considerations when prescribing posaconazole. Many of the medicines used in the same patient population – transplant recipients, haemato-oncology patients and intensive-care patients – are also metabolised by CYP3A4 or transported by P-glycoprotein. A careful interaction review by a clinical pharmacist is recommended at initiation and whenever a new medicine is added or removed.
Absolutely contraindicated combinations
The following combinations must never be given together with posaconazole. Your hospital team will substitute or temporarily stop these medicines before starting Posaconazole Amarox:
| Drug | Category | Clinical risk |
|---|---|---|
| Terfenadine, Astemizole | Antihistamine (older) | QT prolongation, torsades de pointes |
| Cisapride | Prokinetic (GI) | Fatal cardiac arrhythmia |
| Pimozide | Antipsychotic | QT prolongation, sudden cardiac death |
| Halofantrine, Quinidine | Antimalarial / antiarrhythmic | QT prolongation, ventricular arrhythmia |
| Ergotamine, Dihydroergotamine | Migraine / vasoactive | Ergotism, peripheral ischaemia |
| Simvastatin, Lovastatin, Atorvastatin | HMG-CoA reductase inhibitor (statin) | Rhabdomyolysis, acute kidney injury |
| Sirolimus | mTOR inhibitor / immunosuppressant | Extreme rise in sirolimus level; toxicity |
| Venetoclax (ramp-up phase, CLL) | BCL-2 inhibitor | Life-threatening tumour lysis syndrome |
Significant interactions requiring dose adjustment or monitoring
Many frequently used medicines interact with posaconazole but can still be co-prescribed with careful dose adjustment, therapeutic drug monitoring (TDM), or additional clinical surveillance. The table below is not exhaustive:
| Drug / Drug class | Effect with posaconazole | Clinical action |
|---|---|---|
| Tacrolimus (immunosuppressant) | Tacrolimus AUC increased ~3.5 fold | Reduce tacrolimus dose by ~2/3 at start; measure trough levels |
| Ciclosporin (immunosuppressant) | Increased ciclosporin exposure | Reduce dose ~25%; monitor levels and renal function |
| Vincristine, Vinblastine (vinca alkaloids) | Severe neurotoxicity, ileus, SIADH | Avoid if possible; use alternative antifungal during vinca therapy |
| Midazolam, Triazolam, Alprazolam | Prolonged and deeper sedation | Reduce benzodiazepine dose; monitor respiratory status |
| Calcium-channel blockers (diltiazem, verapamil, felodipine) | Hypotension, peripheral oedema | Consider dose reduction; monitor blood pressure |
| Digoxin | Increased digoxin level | Monitor digoxin plasma levels |
| Warfarin, other vitamin-K antagonists | Increased INR and bleeding risk | Check INR more frequently; adjust anticoagulant dose |
| Rifampicin, Rifabutin (enzyme inducers) | Posaconazole exposure markedly reduced | Avoid combination unless benefit outweighs risk; consider TDM |
| Phenytoin, Carbamazepine, Phenobarbital | Reduced posaconazole levels; raised antiepileptic levels | Avoid; if unavoidable, monitor drug concentrations |
| Efavirenz (antiretroviral) | Posaconazole exposure decreased ~50% | Avoid combination when possible |
| Proton pump inhibitors (omeprazole, esomeprazole) | Affects oral suspension absorption (not IV or tablet) | No relevance for IV formulation |
| Ibrutinib, Venetoclax (steady-state) | Significant rise in BTK / BCL-2 inhibitor exposure | Reduce target dose per product label |
| Methotrexate (high-dose) | Possible increased exposure | Monitor methotrexate levels and renal function |
| Antacids, H2-blockers | Reduced absorption of oral suspension only | Not relevant for Posaconazole Amarox IV |
International guidelines (ECIL, IDSA) recommend therapeutic drug monitoring of posaconazole, especially during treatment of invasive fungal infections and in patients with clinically significant drug interactions. A trough plasma concentration of ≥1 mg/L is usually targeted for treatment of invasive aspergillosis, and ≥0.7 mg/L for prophylaxis. The first trough level is typically drawn after 5–7 days of therapy.
What Is the Correct Dosage of Posaconazole Amarox?
The usual adult dose is 300 mg (one vial) twice on the first day (loading dose), followed by 300 mg once daily from day 2 onwards. Each dose is diluted and infused over approximately 90 minutes through a central venous catheter. Patients are switched to oral posaconazole as soon as their condition allows. Children under 13 years should not usually receive the IV formulation.
Posaconazole Amarox should only be prepared and administered by healthcare professionals trained in intravenous chemotherapy or antimicrobial therapy. The vial is a concentrate that must be diluted before infusion – never administered undiluted or as a bolus. Typical dilution instructions are provided in the product label and local hospital protocols.
Adults and adolescents ≥13 years
Standard dosing schedule
Loading dose (day 1): 300 mg twice, approximately 12 hours apart.
Maintenance dose (day 2 onwards): 300 mg once daily.
Infusion duration: approximately 90 minutes via a central venous catheter. Shorter peripheral infusions are not recommended due to the risk of thrombophlebitis.
| Indication | Dose | Typical duration |
|---|---|---|
| Prophylaxis in prolonged neutropenia (AML, MDS) | 300 mg twice on day 1, then 300 mg daily | Throughout neutropenic period and until marrow recovery |
| Prophylaxis in GvHD after HSCT | 300 mg twice on day 1, then 300 mg daily | Until immunosuppression is reduced |
| Invasive aspergillosis (refractory/intolerant) | 300 mg twice on day 1, then 300 mg daily | Minimum 6–12 weeks; based on clinical response |
| Fusariosis (refractory/intolerant) | 300 mg twice on day 1, then 300 mg daily | Until clinical/mycological resolution |
| Chromoblastomycosis, mycetoma | 300 mg twice on day 1, then 300 mg daily | Usually switched to oral therapy as soon as possible (months) |
| Coccidioidomycosis (refractory/intolerant) | 300 mg twice on day 1, then 300 mg daily | Extended; step down to oral therapy when able |
| Oropharyngeal candidiasis (severe) | 300 mg twice on day 1, then 300 mg daily | 13–28 days depending on clinical response |
| Mucormycosis (salvage / step-down, off-label) | 300 mg twice on day 1, then 300 mg daily | Prolonged, often months; guided by imaging and response |
Children (under 13 years)
Pharmacokinetics and safety of the intravenous formulation have not been fully established in children under 13 years of age, and the cyclodextrin excipient has raised theoretical safety concerns in young patients with immature renal function. Posaconazole Amarox is therefore not recommended for routine use in this age group. If antifungal therapy with posaconazole is indicated, specialist paediatric infectious disease teams will consider alternative formulations (oral tablets with food) or alternative antifungals based on age, weight and the specific pathogen.
Older adults
No specific dose adjustment is required based on age alone. Older adults may, however, have reduced renal function and more comorbidities, and should be monitored for electrolyte disturbance, QT prolongation and drug interactions.
Patients with impaired kidney function
No dose adjustment of posaconazole itself is required, because posaconazole is mainly eliminated by the liver. However, the cyclodextrin excipient in the intravenous concentrate is cleared by the kidneys and accumulates in patients with an estimated glomerular filtration rate below 50 mL/min/1.73 m². In this group, the oral formulation should be used whenever possible. If the IV formulation is clinically necessary, serum creatinine should be monitored and the patient switched to oral therapy as early as possible.
Patients with impaired liver function
No specific dose adjustment is recommended for patients with mild, moderate or severe hepatic impairment based on limited data, but caution and enhanced hepatic monitoring are advised, particularly in patients with pre-existing cirrhosis or significant cholestasis.
Missed dose
Because Posaconazole Amarox is administered in hospital on a strict schedule, missed doses are uncommon. If a dose is delayed for logistical reasons, it should be given as soon as possible unless the next scheduled dose is due very shortly, in which case the missed dose should be skipped. A double dose should never be given.
Overdose
There is limited experience with posaconazole overdose. No specific antidote exists. Because posaconazole is highly protein-bound, haemodialysis is unlikely to significantly remove the drug. Management is supportive and symptomatic, with particular attention to cardiac monitoring (QT interval), liver function, and treatment of any concurrent overdose of other drugs that may contribute to toxicity.
What Are the Side Effects of Posaconazole Amarox?
Common side effects include nausea, vomiting, diarrhoea, abdominal pain, headache, fever, low potassium or magnesium levels, raised liver enzymes, and thrombocytopenia. Infusion-site reactions and thrombophlebitis can occur with the IV formulation. Uncommon but serious adverse effects include severe hepatotoxicity, QT prolongation, torsades de pointes, hypersensitivity reactions and adrenal insufficiency. Seek urgent help for jaundice, palpitations, severe rash or signs of anaphylaxis.
Like all medicines, Posaconazole Amarox can cause side effects, although not everyone experiences them. The list below is grouped by frequency using the WHO convention. Because posaconazole is typically used in severely unwell patients who are on many other medications, it can be difficult to distinguish drug-related effects from underlying disease or concomitant therapy.
Contact your medical team or stop the infusion if you experience:
- Sudden chest pain, palpitations, fainting or severe dizziness (possible QT prolongation or arrhythmia)
- Yellowing of skin or eyes, dark urine, severe fatigue or right upper-abdominal pain (possible severe liver injury)
- Widespread rash, blistering, mouth sores or peeling skin (possible severe cutaneous adverse reaction)
- Difficulty breathing, swelling of the lips or throat, hives (possible anaphylaxis)
- Rapidly worsening weakness, fatigue, low blood pressure or hyponatraemia (possible adrenal insufficiency)
Very common side effects
May affect more than 1 in 10 users
- Nausea
- Fever (pyrexia)
- Low potassium level (hypokalaemia)
Common side effects
May affect up to 1 in 10 users
- Headache, dizziness
- Vomiting, diarrhoea, abdominal pain, constipation, dry mouth
- Low platelet count (thrombocytopenia), anaemia, neutropenia
- Low magnesium or calcium, decreased appetite
- Rash, itching
- Raised liver enzymes (ALT, AST, ALP, GGT, bilirubin)
- Infusion-site reactions, thrombophlebitis (IV line)
- Fatigue, asthenia, oedema
- Tingling (paraesthesia), insomnia
- Cough, dyspnoea, nosebleed
- Raised blood pressure
Uncommon side effects
May affect up to 1 in 100 users
- QT interval prolongation on ECG, palpitations, arrhythmia
- Seizures, tremor, neuropathy
- Pancreatitis, gastrointestinal bleeding
- Severe hepatotoxicity, cholestasis, hepatitis
- Adrenal insufficiency, pseudoaldosteronism (hypertension, hypokalaemia, oedema)
- Hypersensitivity reactions, allergic rash, urticaria
- Pulmonary embolism, deep-vein thrombosis
- Visual disturbance, blurred vision
- Haemolytic-uraemic syndrome, thrombotic thrombocytopenic purpura
Rare side effects
May affect up to 1 in 1,000 users
- Torsades de pointes, sudden cardiac arrest
- Stevens-Johnson syndrome, toxic epidermal necrolysis (TEN), DRESS syndrome
- Hepatic failure, fulminant hepatitis
- Severe pseudoaldosteronism
Frequency not known
Cannot be estimated from available data
- Acute generalized exanthematous pustulosis (AGEP)
- Encephalopathy in renally impaired patients (attributed to cyclodextrin accumulation)
Liver effects
Raised liver enzymes are among the most commonly observed laboratory abnormalities with posaconazole. Most cases are mild and reversible after discontinuation. However, serious hepatic reactions including hepatitis, cholestasis and fatal hepatic failure have been reported, often in patients with pre-existing haematological disease or other hepatotoxic co-medications. Liver enzymes and bilirubin should be measured at baseline, after 1 week, then at least monthly during prolonged therapy, or earlier if symptoms of hepatic dysfunction develop.
Cardiac effects
Posaconazole can prolong the QT interval, albeit less frequently than voriconazole. The absolute risk of torsades de pointes is low but not zero, particularly in patients with electrolyte disturbances, bradycardia, female sex, or concomitant QT-prolonging medicines. Baseline ECG, correction of electrolytes and avoidance of additional QT-prolonging drugs are recommended.
Adrenal insufficiency
Rare cases of adrenal insufficiency have been associated with long-term high-dose azole therapy, including posaconazole. Non-specific symptoms such as fatigue, weight loss, hypotension and hyponatraemia should prompt testing of morning cortisol and ACTH levels. Treatment includes corticosteroid replacement and, if possible, discontinuation of the azole.
How Should Posaconazole Amarox Be Stored?
Unopened Posaconazole Amarox vials should be stored in a refrigerator at 2°C to 8°C in the original outer carton to protect from light. Once diluted, the infusion should be used immediately or stored under refrigeration for no longer than 24 hours. It must not be frozen. Pharmacy staff are responsible for correct storage and preparation; patients and caregivers do not handle the product directly.
Posaconazole Amarox is a hospital-use medicine stored in the pharmacy or clinical ward under controlled conditions. Key storage and handling principles include:
- Unopened vials: Store in a refrigerator between 2°C and 8°C (36–46°F), in the original carton, to protect from light. Do not freeze
- After dilution: Chemical and physical in-use stability has been demonstrated for up to 24 hours at 2–8°C. From a microbiological standpoint, the diluted solution should be used immediately; any delayed use is the responsibility of the preparing pharmacy and normally should not exceed 24 hours refrigerated
- Visual inspection: Before infusion, the diluted solution should be inspected visually for particulate matter and discolouration. Any cloudy or discoloured product must be discarded
- Compatibility: Posaconazole Amarox is compatible with 0.9% sodium chloride, 5% dextrose, and several other specified diluents; follow the product label and local pharmacy guidelines for compatible infusion fluids and co-infused drugs
- Disposal: Any unused concentrate, prepared solution, or used administration equipment should be disposed of as pharmaceutical clinical waste in accordance with hospital policy and local regulations. Do not flush into drains or general waste
- Expiry date: Do not use after the expiry date (EXP) printed on the vial and carton. The expiry date refers to the last day of the stated month
What Does Posaconazole Amarox Contain?
The active substance is posaconazole (18 mg per millilitre; 300 mg per 16.7 mL vial). Excipients include betadex sulfobutyl ether sodium (a cyclodextrin solubiliser), disodium edetate, trometamol, hydrochloric acid, sodium hydroxide and water for injections. The product is a clear, colourless to yellow sterile concentrate for solution for infusion.
Active ingredient
Each millilitre of concentrate contains 18 mg of posaconazole. Each vial of 16.7 mL therefore contains 300 mg of posaconazole, which is one full adult dose.
Other ingredients (excipients)
- Betadex sulfobutyl ether sodium (SBECD): a modified cyclodextrin used to solubilise posaconazole in aqueous solution. Each vial contains a substantial amount of this excipient, which is relevant in patients with renal impairment
- Disodium edetate (a chelating agent, stabiliser)
- Trometamol (buffering agent)
- Hydrochloric acid and sodium hydroxide (used for pH adjustment)
- Water for injections
Each vial contains a small amount of sodium from the excipients. Patients on a strictly controlled low-sodium diet should be aware of this. The total sodium load is normally clinically insignificant at standard doses, but should be considered in combination with sodium from other intravenous medicines and fluids.
Appearance and packaging
Posaconazole Amarox is a clear, colourless to pale yellow sterile solution, free of visible particles. It is supplied in a single-dose glass vial containing 16.7 mL of concentrate, sealed with a rubber stopper and aluminium flip-off cap. Pack sizes may vary by country; in most markets single-vial cartons are standard.
Marketing authorisation and manufacturer
Posaconazole Amarox is a generic medicinal product containing the same active substance (posaconazole) as the reference product Noxafil® (originally developed by Schering-Plough, now marketed by Merck Sharp & Dohme / MSD). As a generic, it has been authorised on the basis of bioequivalence to the reference product and meets the same quality, efficacy and safety standards. The exact marketing authorisation holder, batch number and country-specific package information are printed on the outer carton.
Frequently Asked Questions About Posaconazole Amarox
Posaconazole Amarox is a second-generation triazole antifungal given as an intravenous infusion. It is used to prevent invasive fungal infections in people at high risk – including patients receiving chemotherapy for acute myeloid leukaemia or myelodysplastic syndrome and patients with graft-versus-host disease after stem cell transplantation – and to treat invasive aspergillosis, fusariosis, chromoblastomycosis, mycetoma, coccidioidomycosis and refractory oropharyngeal candidiasis. It is also used off-label in some cases of mucormycosis.
Posaconazole Amarox 300 mg concentrate is diluted by hospital pharmacy or trained nursing staff and given as a slow intravenous infusion over approximately 90 minutes through a central venous line. The usual adult schedule is 300 mg twice on day 1 (loading dose), then 300 mg once daily. Patients are usually switched to oral posaconazole tablets or suspension as soon as clinically possible to reduce catheter-related risks and to make outpatient therapy feasible.
Commonly reported side effects include nausea, vomiting, diarrhoea, abdominal pain, headache, fever, low potassium or magnesium levels, raised liver enzymes, thrombocytopenia and anaemia. Infusion-site reactions and thrombophlebitis can occur with the IV formulation. Less common but more serious adverse effects include QT prolongation, severe hepatotoxicity, pancreatitis, hypersensitivity reactions and adrenal insufficiency. Seek urgent medical attention if you develop jaundice, severe rash, chest pain or signs of anaphylaxis.
The intravenous formulation contains a cyclodextrin excipient (betadex sulfobutyl ether sodium) that is cleared by the kidneys and accumulates in patients with moderate to severe renal impairment (eGFR below 50 mL/min/1.73 m²). In these patients the IV formulation should generally be avoided; oral posaconazole tablets or suspension are preferred. If IV therapy is clinically essential, serum creatinine should be monitored closely and the patient switched to oral therapy as soon as feasible.
Posaconazole is a potent inhibitor of cytochrome P450 3A4 (CYP3A4) and of P-glycoprotein, so it can significantly raise blood levels of many co-administered drugs, including sirolimus, tacrolimus, ciclosporin, vincristine, vinblastine, midazolam, simvastatin, atorvastatin, venetoclax and ergot alkaloids. Combinations with sirolimus, pimozide, quinidine, ergot alkaloids and certain statins are contraindicated. Enzyme inducers such as rifampicin, phenytoin or efavirenz can reduce posaconazole exposure. Always share a complete medicine list with your clinical team.
Posaconazole should not be used during pregnancy unless the clinical benefit clearly outweighs the potential risk to the foetus, because animal studies have shown reproductive toxicity and human data are limited. Women of childbearing potential must use effective contraception during treatment. Breastfeeding should be discontinued during therapy with Posaconazole Amarox, as posaconazole is excreted in the milk of lactating animals and there are insufficient human data to establish safety.
Posaconazole is a second-generation triazole with a broader spectrum than fluconazole and itraconazole. Unlike fluconazole, posaconazole is active against Aspergillus species and Mucorales (the fungi that cause mucormycosis). Compared with itraconazole, posaconazole has more predictable intravenous pharmacokinetics, a longer elimination half-life and in some settings a more favourable drug-interaction profile, although it still has many clinically important interactions through CYP3A4 inhibition.
References and Sources
All medical information in this article is based on peer-reviewed scientific literature, international clinical guidelines and official regulatory documents. Our editorial team follows the GRADE evidence framework and adheres to international standards for evidence-based medical communication.
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- U.S. Food and Drug Administration (FDA). Noxafil (posaconazole) – Prescribing Information. Merck Sharp & Dohme; 2024. FDA approved label.
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- Ullmann AJ, Lipton JH, Vesole DH, et al. Posaconazole or fluconazole for prophylaxis in severe graft-versus-host disease. New England Journal of Medicine. 2007;356(4):335–347. doi:10.1056/NEJMoa061098
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Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, composed of licensed physicians, clinical pharmacologists, haematologists and infectious disease specialists with documented academic backgrounds and clinical experience in the management of invasive fungal infections.
Written by licensed physicians with specialisation in clinical pharmacology, haemato-oncology and infectious diseases. All content is based on current international guidelines (EMA, FDA, WHO, ECIL, IDSA, ECMM, BNF) and peer-reviewed research.
Independently reviewed by the iMedic Medical Review Board to ensure accuracy, completeness, and adherence to international medical standards. Evidence level: 1A (systematic reviews and randomised controlled trials).
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