Gliolan

Gliolan is an oral diagnostic agent whose active ingredient is aminolevulinic acid hydrochloride; the product is supplied in a tablet or liquid form (strength not specified) for use in the European market. It belongs to the oncologic diagnostic class and is prescribed by physicians to aid surgeons during fluorescence‑guided resection of malignant glioma. The compound is converted intracellularly to protoporphyrin IX, which fluoresces under blue light, highlighting tumor tissue.

Gliolan is indicated for fluorescence‑guided surgery of malignant glioma, helping neurosurgeons differentiate tumor tissue from normal brain during resection. The agent is administered orally prior to the operative procedure, allowing selective accumulation in tumor cells. - Enhances intraoperative visualization of high‑grade glioma under blue‑light excitation. - Supports more complete tumor removal while preserving surrounding healthy tissue. - Used in conjunction with standard imaging modalities such as MRI for surgical planning. - Applicable to adult patients with suspected or confirmed malignant glioma. - Facilitates documentation of fluorescence patterns for postoperative pathology correlation.

Adverse reactions to Gliolan are generally mild, but rare serious events have been reported; monitoring during and after surgery is recommended. Common: - Transient nausea or vomiting occurring shortly after oral intake of the agent. - Mild headache or dizziness experienced during the surgical procedure under blue light. - Temporary skin discoloration visible at the resection site when illuminated. - Light‑induced visual disturbances such as glare or reduced acuity during fluorescence imaging. Serious: - Severe photosensitivity reactions, including painful erythema, when exposed to intense light sources. - Allergic hypersensitivity manifesting as rash, pruritus, or angioedema requiring medical intervention. - Hepatic enzyme elevations indicating possible liver involvement, monitored via laboratory tests. - Acute renal impairment reported in isolated cases, necessitating renal function assessment.

When prescribing Gliolan, clinicians should evaluate patient history and procedural factors to minimize risk and ensure optimal fluorescence guidance. - Verify absence of known hypersensitivity to aminolevulinic acid or related compounds. - Assess liver and kidney function before administration, as impairment may affect drug metabolism. - Avoid exposure to strong ambient light for several hours after dosing to reduce photosensitivity. - Use appropriate protective eyewear for staff and patient during fluorescence imaging. - Consider pregnancy and lactation status; limited data are available, so weigh potential risks. - Coordinate timing of oral dose with planned surgical start to achieve peak tumor fluorescence.

Gliolan may interact with other agents that influence porphyrin metabolism or photosensitivity; reviewing concomitant medications is recommended. Avoid: - Avoid concurrent use of photosensitizing drugs such as tetracyclines, sulfonamides, or certain chemotherapeutics. - Do not combine with other diagnostic agents that require blue‑light illumination, which could confound fluorescence interpretation. Use with caution: - Use with caution in patients receiving hepatic enzyme inducers or inhibitors, as they may alter protoporphyrin IX accumulation. - Caution is advised when administering anticoagulants, because intraoperative bleeding may affect fluorescence visibility. - Monitor closely when combined with agents that affect renal clearance, especially in patients with reduced kidney function.