What is Gleostine (Lomustine)?
Gleostine (lomustine) is an anti-cancer medication and alkylating agent used in the treatment of brain tumors that are either metastatic or primary and may also be prescribed to treat Hodgkin’s lymphoma alongside additional medications and therapies when those initial treatment methods have proven to be insufficient.
How is Gleostine Used?
Gleostine is taken orally as a single dose once every six weeks. Patients should not take this medication more often than once within a six-week period due to the risk of serious and potentially fatal results of ingesting additional doses of Gleostine.
This medication should be taken on an empty stomach to ensure proper absorption, and most patients are recommended to either take it in the evenings before bed to avoid vomiting or nausea or to take the dose about three hours after a meal, ensuring they do not consume additional foods or snacks for at least one to two hours after taking the medication.
Patients will often be advised to take their dose of Gleostine with an 8-ounce glass of water, but the directions provided by prescribing physicians may vary based on the patient’s condition, symptoms, and other relevant factors. Individuals taking Gleostine should follow their doctor’s exact instructions regarding administration and ingestion of the medication.
Gleostine capsules should be stored at an average temperature of 77°F (25°C) with only temporary exposure to low temperatures not dropping below 59°F (15°C) or high temperatures not exceeding 86°F (30°C).
Keep this medication out of the reach of children and pets at all times.
Due to the cytotoxic nature of Gleostine, this medication should be handled with utmost care to avoid skin or other exposure to the active ingredients. It is recommended that patients or those administering the medications wear protective gloves when handling the medication to avoid potential health risks.
Gleostine capsules should not be broken, and exposure to damaged Gleostine capsules should be avoided.
Pregnant individuals or those who may become pregnant should not be exposed to this medication. These individuals should avoid breathing in any dust that may come from the capsules and should not handle the medication for any reason.
Gleostine is prescribed for the treatment of two primary conditions:
- Brain tumors
- Hodgkin’s lymphoma
This medication is used in the treatment of brain tumors after a patient has already received radiotherapeutic or surgical procedures for their condition. It is used to treat both metastatic as well as primary brain tumors.
For patients diagnosed with Hodgkin’s lymphoma, this medication may be used alongside chemotherapy treatment if their condition has continued to progress after having received their initial chemotherapy treatment.
How Does Gleostine Work?
Gleostine is a type of medication classified as an alkylating agent. This type of medication functions by directly affecting the DNA molecules within the body and preventing the linkage of the DNA’s double helix strands. This effectively causes the strands to break, thereby eliminating the cells.
When this medication is used against cancer cells, it causes them to break apart and become unable to multiply and spread. However, due to the mechanism of action of alkylating agent medications, they must be administered with caution to avoid serious and potentially fatal side effects resulting from their impact on the cells of the body.
Gleostine comes in the form of a capsule with the following strength options:
The most commonly prescribed dosage of Gleostine for both pediatric and adult patients is a single dose of 130 mg/m2 administered every six weeks. Only one dose should be administered orally and should not be repeated until at least six weeks have passed since the prior dose.
Doctors administering this medication are recommended to use doses that round up to the nearest 10 mg, and the prescribed dosage may need to be adjusted if the patient using the medication is simultaneously using additional myelosuppressive medications for treatment.
Patients that have impaired function related to bone marrow should be given a reduced dose of Gleostine every six weeks compared to those receiving the medication under other circumstances related to the condition for which it is being administered as well as any preexisting health conditions. The recommended dose for these individuals is 100 mg/m2 each time the medication is administered.
This medication should never be taken in excess, and patients should not be given additional doses before the end of the six-week period due to the high risk of fatal outcomes as well as severe toxicity.
Taking additional doses and overdosing on Gleostine can result in fatal consequences. Patients who have overdosed or suspect that they may have overdosed on this medication should seek emergency medical attention and contact either their doctor or their local Poison Control Center immediately.
Symptoms of overdose of Gleostine include the following:
- abdominal pain
- abnormal hepatic function
- bone marrow suppression
- infection symptoms
- loss of appetite
- liver issues
- shortness of breath
There are currently no known antidotes for an overdose of Gleostine, so seeking prompt medical attention in the event of an overdose is essential to ensure supportive treatment methods are able to be sufficiently used before the patient experiences severe or fatal repercussions.
The most common side effects of taking Gleostine are as follows:
- hair loss
- loss of appetite
- mouth or lip sores
Many patients taking Gleostine for treatment have reported struggling with intense nausea and vomiting after taking a dose of the medication, and these individuals’ physicians will often prescribe additional medication to help alleviate the symptoms of vomiting and severe nausea. The highest intensity of these side effects typically only lasts for 24 hours, but some patients may have these symptoms continue for several days.
Some of the following more serious side effects may occur and should be reported to your doctor if they occur while taking Gleostine:
- swelling of the feet or legs
- vision changes
Patients that experience any of the following serious side effects while taking Gleostine should seek out immediate medical attention:
- abdominal pain (that doesn’t resolve)
- black stools
- chest pain
- dark urine
- difficulty breathing
- jaundice (yellowing of the skin or eyes)
- pain when breathing
- urine changes (frequency, color)
- vomit that looks similar to coffee grounds
Although rare, there is also the risk of an allergic reaction when taking any medication. If you experience the following symptoms of an allergic reaction after taking Gleostine, seek out emergency medical attention immediately:
- difficulty breathing
- rash on the skin
- swelling of the throat, tongue, mouth, or face
Additionally, Gleostine is also reported to cause optic atrophy and blindness in some individuals. Please consult with your physician regarding the visual risks of taking this medication.
Warnings & Precautions
As a cytotoxic medication, Gleostine has a number of warnings and precautions for those taking the medication or who may be exposed to the medication during handling. Individuals who currently have an infection, are pregnant or may become pregnant, or have a blood disorder or disease of the lungs, liver, or kidneys are those who are most at risk in regard to adverse effects of ingestion or exposure to Gleostine.
A common risk of most anti-cancer medications is myelosuppression, which results in a patient having decreased activity of their bone marrow resulting in a lowered number of platelets, white blood cells, and red blood cells. Gleostine has been closely linked to delayed myelosuppression, which may occur after prolonged treatment or after a patient has already finished treatment with the medication. The patient’s prescribing physician will use regular blood testing to monitor the individual’s blood cells both during and after treatment. A severe decrease in bone marrow activity may be fatal.
Those who are taking or have previously taken Gleostine should report any of the following symptoms of delayed myelosuppression to their doctor immediately:
- black or dark-colored stools
- bleeding gums
- clotting issues
- difficulty breathing
- oral sores
- paleness of the lips, nails, or skin
- rapid heart rate
- red or pink urine
- shaking or shivering
- small purple or red spots on the body
- shortness of breath
- sore throat
- stuffy nose
Patients using Gleostine for treatment will need to have their liver function monitored for the duration of treatment as well as a period after the use of this medication has ended. Gleostine has been proven to increase a patient’s levels of bilirubin, alkaline phosphatase, and transaminases. Those with a history of diabetes, alcohol abuse, hepatitis, or a family history of liver disease are most at risk for developing these abnormalities.
Patients experiencing the following symptoms of hepatotoxicity should report the symptoms to and consult with their prescribing physician:
- abdominal pain
- dark-colored urine
- jaundice (yellowing of the eyes or skin)
- loss of appetite
- light-colored bowel movements
Individuals taking Gleostine who currently have an active infection will likely experience a worsening of that infection due to the impact this medication has on the patient’s white blood cells and overall immunity. Due to the changes that occur in a patient’s immune system when taking this medication, they are also at a higher risk of getting an infection during treatment with Gleostine. Patients taking Gleostine should exercise additional caution when trying to avoid others who may have a contagious condition or infection (e.g., influenza, measles, chickenpox, etc.). If you are currently taking Gleostine and have been exposed to someone with an infection, you should inform your doctor as soon as possible.
Due to this medication resulting in impaired immunity, it is advised that these individuals do not receive any vaccinations or immunizations during treatment. However, if such proactive treatments as these are deemed medically necessary for the individual, they should be sure to inform their physician that they are currently using Gleostine for treatment before receiving any immunizations. Additionally, patients taking Gleostine that have an impaired immune system should avoid exposure to other individuals who have recently received any live vaccines (e.g., the intranasal flu vaccine).
Gleostine has been linked to patients experiencing a decrease in kidney size and progressive renal failure after receiving treatment with this medication. Those with a history of kidney disease or other kidney-related conditions should discuss this aspect of their medical history with their doctor before beginning treatment with this medication. Patients using Gleostine should have their renal function monitored for the duration of treatment as well as a period after treatment has stopped.
Pregnancy and Breastfeeding
Individuals who are pregnant are strongly advised against using this medication during pregnancy. Those who may become pregnant should either not take Gleostine or take appropriate measures to prevent pregnancy throughout the duration of their treatment with this medication. The minimum recommendations for those who remain sexually active during treatment with Gleostine are to use multiple forms of birth control throughout the duration of treatment as well as for a two-week period afterward. Generally, these practices should be continued for at least four months after treatment has ended to ensure a reduced and ideally nonexistent risk of harm to an unborn child conceived by a partner who has been treated with Gleostine. The impacts of Gleostine on a patient’s reproductive health while using this medication apply to both male and female patients.
Those currently taking Gleostine who become pregnant or suspect they may be pregnant should contact their doctor immediately.
Those who are currently pregnant and at risk of exposure to this medication should exercise extreme caution and avoid handling the medication as well as breathing in any dust from the capsules to avoid harm occurring to the unborn child.
It has not been determined whether this medication is passed through breastmilk, so patients taking Gleostine who may want to breastfeed a child should consult their physician before doing so. Often, it is recommended that breastfeeding be avoided during treatment with Gleostine and for a period of at least two weeks after treatment has ended.
The use of Gleostine has been linked to a high risk of pulmonary toxicity, especially in patients who have already finished treatment with the medication. The effects of this medication on the lungs may result in lung damage stemming from inflammation or scarring. This damage may either impact the patient’s ability to breathe in enough air or cause a reduction in the amount of oxygen that may be absorbed by the lungs. Patients who are currently taking or have previously taken Gleostine that develop symptoms such as chest pain, difficulty breathing, cough, or pain when trying to breathe should report these symptoms to their physician and seek emergency medical attention.
The long-term use of Gleostine for treatment has been commonly linked to the development of secondary malignancies, specifically myelodysplasia and acute myeloid leukemia. These conditions are most likely to develop within three to five years of exposure to medications such as Gleostine, with a decreased risk of development once a patient has reached the ten-year mark.
Additional Medical Conditions
If you have any of the following medical conditions, exercise caution when taking Gleostine and discuss your medical history with your doctor before beginning this medication:
- an active infection
- blood disorders
- kidney disease
- liver disease
- lung disease
- risk of pregnancy
Speak to your doctor about any medications or herbal supplements you are currently taking before beginning treatment with Gleostine. Discuss any concerns you may have with your doctor or a trusted pharmacist.
Although no specific medications are currently contraindicated with the use of Gleostine, those who have a medical history of kidney, liver, or lung disease that may be taking medications for these conditions should consult with their doctor regarding any potential modifications that may need to take place during treatment with Gleostine to ensure that their current medications and medical conditions remain appropriately treated.
For patients who are unable to take Gleostine or experiencing significant adverse side effects, alternative medications may be used to treat some of the associated conditions for which this medication is commonly prescribed:
- procarbazine (Matulane)
- vincristine (Marqibo, Vincasar PFS)
Additionally, there are other brand-name medications of lomustine available that a patient may be prescribed: