Iscador M
European Mistletoe Extract for Adjuvant Palliative Cancer Care
Iscador M is a plant-based medicinal product derived from fermented European mistletoe (Viscum album L.) grown on apple trees. It is used as an adjuvant in individualised palliative cancer care alongside conventional treatments. Administered by subcutaneous injection, Iscador M is believed to support the immune system and improve quality of life in cancer patients. This prescription-only medicine requires careful medical supervision and is not suitable for all patients.
Quick Facts
Key Takeaways
- Iscador M is a fermented mistletoe extract used as an adjuvant in palliative cancer therapy, not as a standalone cancer treatment.
- It is administered by subcutaneous injection with a gradual dose-escalation protocol under medical supervision.
- The product is contraindicated in patients with active infections, autoimmune diseases, granulomatous diseases, or known hypersensitivity to mistletoe.
- Local injection site reactions (redness, mild swelling) are expected; reactions exceeding 5 cm diameter require treatment discontinuation and medical consultation.
- Iscador M must not be used during pregnancy or breastfeeding, and is not approved for patients under 18 years of age.
What Is Iscador M and What Is It Used For?
Quick Answer: Iscador M is a plant-based medicinal product containing a fermented extract of European mistletoe (Viscum album L.) harvested from apple trees. It is used as an adjuvant in individualised palliative cancer care alongside conventional therapies such as surgery, chemotherapy, and radiotherapy.
Iscador M belongs to a class of medicines known as mistletoe preparations (Viscum album preparations), which have been used in integrative oncology for over a century, primarily in Central European countries. The product is manufactured from fresh European mistletoe plants (Viscum album L. ssp. album) that grow on apple trees (Malus domestica Borkh.), using a proprietary fermentation process. This fermentation is designed to extract and concentrate the biologically active compounds present in the mistletoe plant, including mistletoe lectins (viscumin), viscotoxins, flavonoids, and other glycoproteins.
The primary therapeutic application of Iscador M is as an adjuvant in palliative cancer care. This means it is not intended to cure cancer on its own, but rather to complement standard oncological treatments. The goal of Iscador M therapy is to support the patient's immune system, potentially improve quality of life, and help manage symptoms associated with both the disease and its conventional treatments. Clinical studies have investigated whether mistletoe preparations may help reduce the side effects of chemotherapy and radiation therapy, potentially improving patients' ability to tolerate these treatments.
The immunomodulatory properties of Iscador M are attributed to its biologically active compounds. Mistletoe lectins are known to bind to cell surface glycoconjugates and may induce apoptosis (programmed cell death) in certain tumour cell lines under laboratory conditions. Additionally, Viscum album extracts have demonstrated the ability to stimulate natural killer (NK) cells, T-helper cells, and the production of cytokines including interleukin-1 (IL-1), interleukin-6 (IL-6), and tumour necrosis factor alpha (TNF-alpha). These immunostimulatory effects are believed to be central to the proposed mechanism of action in cancer patients receiving palliative care.
There are three main variants of Iscador, each derived from mistletoe grown on different host trees: Iscador M (apple tree), Iscador P (pine tree, Pinus sylvestris), and Iscador Qu (oak tree, Quercus robur). The choice of which variant to prescribe is determined by the treating physician based on the individual patient's clinical picture, the type and location of the cancer, and the patient's overall health status. The prescribing philosophy follows an individualised approach, which is a hallmark of the anthroposophic medical tradition from which mistletoe therapy originates.
Iscador M is not a substitute for conventional cancer treatment. It should only be used under the supervision of a qualified physician experienced in mistletoe therapy, and always in conjunction with standard oncological care including surgery, chemotherapy, radiotherapy, or targeted therapy as appropriate.
What Should You Know Before Using Iscador M?
Quick Answer: Iscador M is contraindicated in patients with hypersensitivity to mistletoe, active infections with fever, granulomatous diseases, autoimmune disorders, and those recently treated with immunosuppressive drugs. It must not be used during pregnancy or breastfeeding.
Contraindications
There are several important contraindications and precautions to be aware of before starting treatment with Iscador M. Understanding these restrictions is essential for patient safety and optimal therapeutic outcomes.
Do not use Iscador M if any of the following apply:
- Hypersensitivity: If you are allergic (hypersensitive) to mistletoe or any other component of this medicine, including sodium chloride or water for injections, you must not use Iscador M. Allergic reactions can range from mild skin irritation to severe systemic reactions.
- Acute inflammation or infection with fever: If you are experiencing an acute inflammatory condition or infection accompanied by a temperature above 38°C (100.4°F), treatment with Iscador M should be interrupted until the inflammatory symptoms have fully resolved. The immunostimulatory action of mistletoe extracts could potentially worsen an existing inflammatory or infectious process.
- Granulomatous diseases: Patients with granulomatous conditions such as sarcoidosis should not use Iscador M. Chronic granulomatous inflammation, including sarcoidosis and erythema nodosum, has been described during mistletoe therapy, suggesting that the immunomodulatory effects may exacerbate these conditions.
- Autoimmune diseases: Iscador M is contraindicated in patients with autoimmune disorders. Dermatomyositis has been reported during mistletoe therapy, and the immune-stimulating properties of Viscum album preparations may theoretically worsen autoimmune conditions by further activating the immune system against the body's own tissues.
- Recent immunosuppressive therapy: If you have recently used medications that suppress the immune system (immunosuppressants), you should discuss this with your doctor before starting Iscador M. The interaction between immunosuppressive and immunostimulatory agents may produce unpredictable effects.
Warnings and Precautions
Speak with your doctor or pharmacist before using Iscador M in the following situations:
Brain and spinal cord tumours: If you have a primary brain or spinal cord tumour, or brain metastases that carry a risk of increased intracranial pressure, Iscador M should only be used if your doctor has specifically prescribed it for your condition. Symptoms of increased intracranial pressure have been described during mistletoe treatment of brain tumours and metastases, which could lead to serious neurological complications.
During chemotherapy or radiation therapy: More pronounced reactions to the injections are possible during or immediately after chemotherapy or radiotherapy. Special caution should therefore be exercised, and doses should be increased carefully and gradually during these treatment periods. Your oncologist should be aware that you are receiving Iscador M alongside conventional cancer treatments to allow for appropriate dose adjustments and monitoring.
Hyperthyroidism: In patients with an overactive thyroid gland (hyperthyroidism) accompanied by a high pulse rate, the use of Iscador M should be avoided. The immunostimulatory effects of mistletoe extracts may interact with the already hypermetabolic state associated with hyperthyroidism.
Pregnancy and Breastfeeding
If you are pregnant, think you may be pregnant, are breastfeeding, or are planning to become pregnant, you should not use Iscador M. The safety of mistletoe preparations during pregnancy and breastfeeding has not been established, and the immunomodulatory effects of Viscum album extracts could potentially affect foetal development or be transmitted through breast milk. Women of childbearing age should discuss appropriate contraception with their healthcare provider while receiving mistletoe therapy.
Driving and Using Machines
Iscador M has no or negligible effect on the ability to drive and use machines. However, you are personally responsible for assessing whether you are fit to operate motor vehicles or perform tasks requiring alertness. Some patients may experience transient flu-like symptoms after injection, which could theoretically affect concentration. If you experience any side effects that might impair your ability to drive safely, refrain from driving until the symptoms resolve.
This medicine contains less than 1 mmol sodium (23 mg) per dose, meaning it is essentially sodium-free. This is relevant for patients on a sodium-restricted diet.
How Does Iscador M Interact with Other Drugs?
Quick Answer: Formal drug interaction studies for Iscador M have not been conducted. However, given its immunomodulatory mechanism, theoretical interactions exist with immunosuppressive agents and other immunomodulatory therapies. Always inform your doctor about all medications you are taking.
The potential effects of simultaneous use of Iscador M with other medications have not been formally investigated in controlled clinical studies. This is an important limitation that patients and healthcare providers should be aware of. Because Iscador M acts primarily through immunomodulatory mechanisms, the greatest concern relates to potential interactions with drugs that also affect the immune system.
Always inform your doctor or pharmacist if you are using, have recently used, or might use any other medications, including over-the-counter medicines, herbal supplements, and vitamins. This information is essential for your healthcare provider to assess the potential for interactions and adjust your treatment plan accordingly.
Theoretical Interactions
Although no formal interaction studies have been performed, healthcare professionals should consider the following theoretical interactions based on the pharmacological profile of mistletoe extracts:
| Drug / Drug Class | Type of Interaction | Clinical Significance | Recommendation |
|---|---|---|---|
| Immunosuppressants (e.g. ciclosporin, tacrolimus, methotrexate) | Pharmacodynamic antagonism | The immunostimulatory effects of mistletoe may counteract immunosuppressive therapy | Avoid concurrent use; discuss with prescribing physician |
| Checkpoint inhibitors (e.g. nivolumab, pembrolizumab) | Additive immune stimulation | Potential for increased autoimmune-like adverse effects | Use with extreme caution; close monitoring required |
| Corticosteroids (e.g. prednisolone, dexamethasone) | Pharmacodynamic antagonism | High-dose corticosteroids may reduce efficacy of Iscador M | Inform your doctor; dosage adjustment may be needed |
| Other immunomodulators (e.g. interferons, interleukins) | Additive or synergistic immunostimulation | Unpredictable enhancement of immune responses | Use only under specialist supervision |
| Thyroid hormones (e.g. levothyroxine) | Theoretical metabolic interaction | May affect thyroid function monitoring | Monitor thyroid function; inform your doctor |
Do not start or stop any medication without consulting your doctor. Because formal interaction studies have not been conducted for Iscador M, the absence of a documented interaction does not guarantee safety when combining with other drugs. Your treating oncologist should always be informed about your use of Iscador M.
What Is the Correct Dosage of Iscador M?
Quick Answer: Iscador M dosing follows an individualised, gradual dose-escalation protocol determined by your physician. Treatment typically begins with low-strength preparations (0.01 mg) and increases over time to the highest tolerated dose. The injection is given subcutaneously, usually 2–3 times per week.
Always use this medicine exactly as your doctor has told you. Check with your doctor if you are not sure. The dosage of Iscador M is highly individualised, and your physician will determine the appropriate dose, injection frequency, and treatment duration based on your specific clinical situation, the type and stage of your cancer, and your tolerance to the therapy.
Adults
The standard treatment protocol for Iscador M in adults follows a structured dose-escalation approach:
Initial Phase (Dose Escalation)
Treatment usually begins with the lowest strength (0.01 mg) and gradually increases through intermediate strengths (0.1 mg, 1 mg) towards higher doses (10 mg, 20 mg). The rate of dose escalation is determined by the physician based on the patient's tolerance and clinical response. Starter packs containing a combination of three strengths are available to facilitate the initial dose-escalation phase.
Maintenance Phase
After successful dose escalation, the physician transitions to a maintenance regimen using the highest dose that was best tolerated during the initial phase. This dose is typically administered 2–3 times per week by subcutaneous injection. The maintenance dose should be reviewed every 3 to 6 months to ensure continued appropriateness.
| Pack Type | Strengths Included | Ampoule Configuration | Typical Use |
|---|---|---|---|
| Starter Pack 1 | 0.01 mg + 0.1 mg + 1 mg | 2 + 2 + 3 ampoules (7 total) | Initial dose escalation |
| Starter Pack 2 | 0.1 mg + 1 mg + 10 mg | 2 + 2 + 3 ampoules (7 total) | Continued escalation |
| Starter Pack 3 | 1 mg + 10 mg + 20 mg | 2 + 2 + 3 ampoules (7 total) | High-dose escalation |
| Maintenance Pack | 1 mg, 10 mg, or 20 mg (single strength) | 7 ampoules | Ongoing maintenance therapy |
Injection Technique
Iscador M is intended for subcutaneous use (injection under the skin) at various sites with intact, undamaged skin. Common injection sites include the abdomen, the front or outer aspect of the thigh, and areas near the tumour site where possible. Your doctor or nurse will demonstrate the correct injection technique, and you should follow their instructions carefully.
Important injection guidelines include:
- Do not inject into inflamed skin areas, such as sites showing inflammation from previous injections or areas with vein inflammation (phlebitis).
- Avoid injecting into irradiated skin areas.
- Ampoules should not be injected while still cold from the refrigerator; warm the ampoule briefly in your hand before use.
- Opened ampoules must not be saved for future injections; discard any unused portion.
- Rotate injection sites regularly to minimise local reactions.
Children and Adolescents
Iscador M should not be used by children and adolescents under 18 years of age. There is insufficient evidence on the safety and efficacy of mistletoe preparations in paediatric populations, and no paediatric dosing recommendations are available.
Missed Dose
If you forget to administer an injection, do not take a double dose to compensate. Simply continue with the regular dose scheduled for the next injection. Missing an occasional dose is unlikely to significantly affect the overall course of treatment, but try to maintain the prescribed schedule as consistently as possible.
Overdose
If you have administered too much Iscador M, or if a child has accidentally received the medicine, contact your doctor, hospital, or poison control centre immediately for an assessment of the risk and advice. Symptoms of overdose may include exaggerated local reactions, systemic inflammatory symptoms (fever, chills, malaise), and potentially other adverse effects.
Treatment Interruption and Resumption
No maximum treatment duration has been established for Iscador M. The length of treatment is determined by your doctor based on your health status and clinical response. However, if you have interrupted treatment for more than 4 weeks, you should contact your doctor before resuming. It may be necessary to restart the dose-escalation process from a lower strength to avoid excessive reactions. Do not change the established dose on your own; if you feel the medicine is having too strong or too weak an effect, consult your doctor.
What Are the Side Effects of Iscador M?
Quick Answer: The most common side effects of Iscador M include local injection site reactions (redness, swelling, hardening) and flu-like symptoms. Allergic reactions, including anaphylaxis, are rare but possible. Chronic granulomatous inflammation and autoimmune-like reactions have been reported during mistletoe therapy.
Like all medicines, Iscador M can cause side effects, although not everybody gets them. The side effect profile of mistletoe preparations is generally characterised by local reactions at the injection site and, less frequently, systemic effects. Understanding these potential effects is important for appropriate monitoring and management of therapy.
Local injection site reactions such as mild redness, slight swelling, and warmth at the injection site are actually considered a normal part of the therapeutic response and may indicate activation of the immune system. However, certain types and severities of reactions require medical attention and may necessitate treatment modification or discontinuation.
Common Side Effects
May affect up to 1 in 10 people
- Local injection site reactions: redness, swelling, warmth, and tenderness at the injection site
- Subcutaneous induration (hardening under the skin) at the injection site
- Mild elevation in body temperature (low-grade fever)
- Flu-like symptoms: malaise, chills, headache
- Joint and limb pain following injection
Uncommon Side Effects
May affect up to 1 in 100 people
- Generalised pruritus (itching)
- Urticaria (hives) or skin rash
- Activation of previously existing inflammations
- Inflammatory irritation of superficial veins near the injection area (phlebitis)
- Localised swelling (e.g. lip or throat swelling)
Rare Side Effects
May affect up to 1 in 1,000 people
- Severe allergic (anaphylactic) reactions including chills, dyspnoea, bronchospasm, and, very rarely, anaphylactic shock
- Chronic granulomatous inflammation (sarcoidosis, erythema nodosum)
- Autoimmune reactions (dermatomyositis has been reported)
- Symptoms of increased intracranial pressure (in patients with brain tumours or metastases)
Discontinue Iscador M and contact your doctor immediately if you experience any of the following:
- Injection site inflammation (redness, swelling, or subcutaneous hardening) with a diameter greater than 5 cm
- Fever above 38°C (100.4°F) occurring in connection with the injection
- Flu-like symptoms: general malaise, chills, headache, joint pain, or limb pain after injection
- Signs of an allergic reaction: widespread itching, hives, swelling of the lips or throat, difficulty breathing, or feeling faint
- Neurological symptoms such as severe headache, visual disturbances, or altered consciousness (especially in patients with brain tumours)
These allergic and hypersensitivity reactions require that the product is discontinued immediately and, if necessary, appropriate medical treatment is initiated. If you develop symptoms of chronic granulomatous inflammation or autoimmune disease during Iscador M therapy, treatment should be stopped and you should be evaluated by your healthcare provider.
Reporting Side Effects
It is important to report suspected adverse reactions after the medicine has been authorised. This allows continued monitoring of the medicine's benefit-risk balance. Healthcare professionals and patients are encouraged to report any suspected side effects to their national medicines regulatory authority. Reporting helps to improve the safety monitoring of all medicines and contributes to better understanding of the long-term safety profile of mistletoe preparations.
How Should You Store Iscador M?
Quick Answer: Store Iscador M in a refrigerator at 2°C–8°C (36°F–46°F). Keep out of the sight and reach of children. Do not use after the expiry date printed on the ampoule and outer packaging.
Proper storage of Iscador M is essential to maintain the quality and efficacy of the product. The biologically active compounds in mistletoe extracts are sensitive to temperature, and improper storage may reduce the potency or safety of the preparation.
- Temperature: Store in a refrigerator at 2°C to 8°C (36°F to 46°F). Do not freeze. Do not expose to direct sunlight or excessive heat.
- Accessibility: Keep this medicine out of the sight and reach of children at all times.
- Expiry date: Do not use Iscador M after the expiry date (EXP) printed on the ampoule and the outer packaging. The expiry date refers to the last day of that month.
- Before injection: Ampoules taken from the refrigerator should be warmed briefly in the hand before injection. Cold injections may be more uncomfortable and may affect absorption.
- Opened ampoules: Opened ampoules must not be stored for subsequent injections. Discard any unused portion immediately after use.
- Disposal: Do not dispose of medicines via wastewater or household waste. Ask your pharmacist how to dispose of medicines that are no longer required. These measures help to protect the environment.
What Does Iscador M Contain?
Quick Answer: The active substance is a fermented extract of European mistletoe (Viscum album L. ssp. album) from apple trees, available in five strengths ranging from 0.01 mg to 20 mg per 1 ml ampoule. The other ingredients are water for injections and sodium chloride.
Active Substance
The active ingredient in Iscador M is a fermented aqueous extract of Viscum album L. ssp. album (European mistletoe), harvested from the host tree Malus domestica Borkh. (apple tree). The extract contains a complex mixture of bioactive compounds including mistletoe lectins, viscotoxins, flavonoids, polysaccharides, and other plant-derived glycoproteins. The relationship between extract quantity and equivalent fresh mistletoe content varies by strength:
| Strength | Extract Content | Fresh Mistletoe Equivalent | Appearance |
|---|---|---|---|
| 0.01 mg | 0.05 mg | 0.01 mg | Clear, colourless solution |
| 0.1 mg | 0.5 mg | 0.1 mg | Clear, colourless solution |
| 1 mg | 5 mg | 1 mg | Clear, colourless to light yellow solution |
| 10 mg | 50 mg | 10 mg | Clear, light yellow to yellow solution |
| 20 mg | 100 mg | 20 mg | Clear, yellow solution |
Other Ingredients (Excipients)
The formulation contains only two excipients: water for injections (serving as the solvent) and sodium chloride (to achieve isotonicity with body fluids, making the injection more comfortable). The sodium content is less than 1 mmol (23 mg) per dose, which is considered essentially sodium-free.
Packaging
Iscador M is supplied in glass ampoules, each containing 1 ml of solution for injection. The ampoules are packaged in cartons containing 7 ampoules per box. Not all pack sizes or strength combinations may be marketed in all countries. The manufacturer is Iscador AG, based in Lörrach, Germany.
Frequently Asked Questions About Iscador M
Iscador M is a plant-based medicinal product used as an adjuvant in individualised palliative cancer care. It is administered alongside conventional cancer therapies such as surgery, chemotherapy, and radiation therapy. The aim is to support the immune system and improve quality of life in cancer patients. It is not used as a standalone cancer treatment and should only be prescribed by a physician experienced in mistletoe therapy.
Iscador M is given as a subcutaneous injection (under the skin), typically near the tumour site. Common injection sites include the abdomen and the front or outer thigh. Treatment usually begins with low doses that are gradually increased. Patients or caregivers can be trained to administer the injections at home after initial instruction from a healthcare professional. The ampoule should be warmed briefly in the hand before injection.
The three Iscador variants differ in their host tree source. Iscador M is derived from mistletoe grown on apple trees (Malus domestica), Iscador P from mistletoe grown on pine trees (Pinus sylvestris), and Iscador Qu from mistletoe grown on oak trees (Quercus robur). The host tree influences the composition and concentration of biologically active compounds in the extract. The choice of variant is determined by the prescribing physician based on the individual patient's condition, the type of cancer, and the overall clinical picture.
Iscador M can be used during chemotherapy or radiation therapy, but special caution is required. More pronounced injection site reactions are possible during or immediately after these treatments. Doses should be increased carefully and gradually during these periods. Some clinical studies have investigated whether mistletoe therapy may help reduce the side effects of conventional cancer treatment, but this should always be managed under close medical supervision. Always inform your oncologist that you are using Iscador M.
Mild redness and slight swelling at the injection site are considered a normal part of the therapeutic response and may indicate immune system activation. However, if the inflammation at the injection site (redness, swelling, or subcutaneous hardening) exceeds 5 cm in diameter, you must discontinue treatment and contact your doctor. Likewise, stop treatment and seek medical advice if you develop fever or flu-like symptoms (chills, headache, joint pain, limb pain) after the injection. Your doctor will determine whether and how to continue therapy.
No, Iscador M is not recommended for use in children and adolescents under 18 years of age. There is insufficient clinical evidence on the safety and efficacy of mistletoe preparations in paediatric populations, and no specific dosing guidelines exist for this age group. Treatment with Iscador M should only be initiated by a qualified physician for adult patients.
References & Sources
This article is based on peer-reviewed clinical research, official product information, and international medical guidelines. All sources are from reputable medical institutions and peer-reviewed journals.
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Editorial Team
This article has been written and reviewed by the iMedic Medical Editorial Team, comprising board-certified physicians specialising in oncology, integrative medicine, and clinical pharmacology. All content follows international medical guidelines and is reviewed according to the GRADE evidence framework.
iMedic Medical Editorial Team – Oncology and Integrative Medicine specialists with clinical and research experience in cancer supportive care.
iMedic Medical Review Board – Independent panel of medical experts reviewing all content according to WHO, ESMO, and ASCO guidelines.
Last medical review: . Next scheduled review: . All medical information is independently produced with no commercial funding or pharmaceutical sponsorship.