Gliolan

Gliolan is an oral powder for solution containing the active ingredient aminolevulinic acid hydrochloride; the specific strength is not disclosed. It is a prescription‑only prodrug and photosensitizer marketed in the European Union for use in fluorescence‑guided surgery. After oral administration, the compound is metabolized to protoporphyrin IX, which accumulates in tumor cells of malignant gliomas and emits fluorescence under blue light, aiding neurosurgeons during resection in patients.

Gliolan is indicated for fluorescence‑guided resection of malignant glioma during neurosurgical procedures.

- Enhances intra‑operative visualization of tumor tissue under blue‑light excitation. - Assists surgeons in distinguishing tumor margins from surrounding healthy brain tissue. - Supports maximal safe resection while preserving functional cortex. - Can be combined with standard imaging modalities such as MRI or neuronavigation for comprehensive surgical planning. - Used in adult patients with suspected or confirmed high‑grade glioma.

Adverse reactions reported with Gliolan are generally related to its photosensitizing properties and to systemic exposure to the prodrug.

Common: - Transient nausea or vomiting after oral intake. - Mild headache or dizziness during the procedure. - Temporary skin photosensitivity resulting in mild erythema when exposed to strong light. - Elevated liver enzymes that resolve without intervention.

Serious: - Severe photosensitivity leading to blistering or ulceration of exposed skin. - Anaphylactic or severe hypersensitivity reactions, including rash, bronchospasm, or hypotension. - Acute hepatic injury manifested by marked transaminase elevation and jaundice.

When prescribing Gliolan, clinicians should evaluate patient-specific factors and follow safety measures to minimize risks.

- Confirm diagnosis of malignant glioma and suitability for fluorescence‑guided surgery. - Perform baseline liver function tests; avoid use in patients with severe hepatic impairment. - Advise patients to avoid direct sunlight and intense indoor lighting for 24‑48 hours after dosing. - Ensure adequate hydration to reduce the risk of renal concentration of the drug. - Review any history of photosensitivity disorders or porphyria before administration. - Monitor for signs of allergic reaction during and after infusion. - Use protective eye coverings during illumination to prevent ocular phototoxicity.

Gliolan may interact with other medications or substances that affect photosensitivity, hepatic metabolism, or porphyrin pathways.

Avoid: - Concomitant use of other photosensitizing agents such as tetracyclines, sulfonamides, or psoralen derivatives. - Strong CYP450 inducers that could reduce aminolevulinic acid exposure (e.g., rifampin, carbamazepine). - Medications known to precipitate porphyria attacks, including certain antiepileptics. - High‑dose vitamin A supplements, which may increase photosensitivity.

Use with caution: - Anticoagulants, because intra‑operative bleeding may be influenced by surgical visualization. - Drugs affecting liver function (e.g., acetaminophen overdose) that could alter drug metabolism. - Anesthetic agents that may mask early signs of hypersensitivity. - Diuretics that may affect renal clearance of metabolites.