Nitrosourea alkylating agent Pregnancy: US §8.1: based on animal data and its mechanism of action, lomustine can cause foetal harm when administered to a pregnant woman; no data on exposure in pregnant women. Lomustine was teratogenic in rats and embryotoxic in rabbits. Advise pregnant women of the potential risk to a foetus, and advise males and females of reproductive potential to use effective contraception (§5.7).

Lomustine (Specialist drug)

Brand names: CCNU

Lomustine is an oral nitrosourea alkylating cytotoxic used, under specialist supervision, in the treatment of certain brain tumours and Hodgkin lymphoma.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 130 mg/m2 as a SINGLE oral dose every 6 weeks (round the dose to the nearest 10 mg)

Route: Oral (capsules; do not break capsules — cytotoxic, wear impervious gloves when handling)

Frequency: Single dose every 6 weeks; do not repeat for at least 6 weeks

Max: One dose per treatment cycle only — prescribe and dispense only a single dose (not the entire container) and do not give more frequently than every 6 weeks. Taking more than the recommended dose causes toxicities, including fatal outcomes.

NO UK SPC WAS AVAILABLE IN THE FETCHED BUNDLE — dose taken from the US prescribing information (Gleostine, Azurity Pharmaceuticals, label date 2025-09-25). US §2.2: 'The recommended dose of Gleostine in adult and pediatric patients is 130 mg/m2 taken as a single oral dose every 6 weeks. Round doses to the nearest 10 mg... Reduce dose to 100 mg/m2 every 6 weeks in patients with compromised bone marrow function. Also reduce dose accordingly when using with other myelosuppressive drugs.' DOSE MODIFICATION (§2.3): perform weekly complete blood counts; withhold each subsequent dose beyond 6 weeks if needed until platelets recover to >=100,000/mm3 and leukocytes to >=4000/mm3. Modify each dose according to the nadir after the prior dose — leukocyte nadir >=4000/mm3 or platelets >=100,000/mm3: no change; leukocytes 3000-3999 or platelets 75,000-99,999: no change; leukocytes 2000-2999 or platelets 25,000-74,999: reduce dose by 30%; leukocytes <2000 or platelets <25,000: reduce dose by 50%. Monitor blood counts for at least 6 weeks after each dose — myelosuppression is delayed (usually 4-6 weeks after administration), dose-related and cumulative, persisting 1-2 weeks, with thrombocytopenia generally more severe than leukopenia. Perform pulmonary function tests before treatment and repeat frequently; permanently discontinue if pulmonary fibrosis is diagnosed. Monitor liver and renal function. PAEDIATRIC (per m2, not per kg, so not captured in paedDose): the US label gives the same recommended dose of 130 mg/m2 as a single oral dose every 6 weeks in 'adult and pediatric patients', but §8.4 states 'Pediatric use, including dose, is not based on adequate and well-controlled clinical studies.' Verify against a children's formulary and local protocol before use in under-18s. ELDERLY (§8.5): no clinical study data in patients 65 years and over; dose selection should be cautious, reflecting greater frequency of decreased hepatic, renal or cardiac function; monitor renal function. Clinician to confirm the UK licensed posology against the current SPC before publication.

Dose adjustments

Renal

US §8.5: lomustine and its metabolites are known to be substantially excreted by the kidney and the risk of toxic reactions may be greater in patients with impaired renal function — care should be taken in dose selection and renal function should be monitored. No numeric renal dose-reduction schedule is given in the fetched labelling; §5.6 notes lomustine can cause renal failure and that renal function should be monitored.

Dose auto-extracted from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

US labelling §4 states 'None.' (no UK SPC §4.3 available in the fetched bundle — clinician to verify)

Side effects

Delayed myelosuppression — dose-related and cumulative, usually 4 to 6 weeks after administration and persisting 1 to 2 weeks; can result in fatal infections and bleeding; thrombocytopenia generally more severe than leukopenia
Nausea, vomiting and stomatitis
Alopecia
Pulmonary toxicity — pulmonary infiltrates and/or fibrosis (permanently discontinue if fibrosis is diagnosed)
Hepatotoxicity (raised transaminases, alkaline phosphatase and bilirubin) and nephrotoxicity including renal failure
Secondary malignancies — acute leukaemia and myelodysplasia with long-term use
Ocular: optic atrophy, visual disturbances, blindness. Neurological: disorientation, lethargy, ataxia, dysarthria

Interactions

Other myelosuppressive drugs: 'reduce dose accordingly when using with other myelosuppressive drugs' (US §2.2). No dedicated drug-interactions section was present in the fetched bundle — clinician to source §4.5 from the UK SPC.

Clinical monograph

How it works

It alkylates and carbamoylates DNA, causing cross-linking that disrupts DNA replication and transcription, and is lipophilic enough to cross the blood-brain barrier.

Prescribing in practice

Causes delayed, cumulative and potentially severe bone-marrow suppression (notably delayed thrombocytopenia and leukopenia), so courses are given at long intervals and a full blood count must be checked before each course.
It is given as a single oral dose repeated only after an extended interval, and fatal overdose has occurred when patients took it more frequently than prescribed — dispensing and counselling must guard against this.
Cumulative dosing is associated with pulmonary fibrosis and nephrotoxicity, so lifetime exposure is monitored and lung and renal function reviewed.

Monitoring

Monitor full blood count before each course and for a prolonged period afterwards, with periodic liver, renal and pulmonary function assessment over cumulative therapy.

Counselling the patient

Take only the dose your specialist team prescribes and never repeat it early — taking it more often than instructed can be fatal.
Report fever, unusual bruising or bleeding, breathlessness or persistent cough promptly.
Effective contraception is needed during and after treatment as the drug can harm a pregnancy.

Evidence & guidelines

Use is supported by established oncology practice and the SPC; treatment should follow specialist protocols.

Reference: SmPC; 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).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways