Gliolan

Last edited and medically reviewed by Alaric Steinmetz on 07.02.2026

Synonyms

5-ALA, Gliolan, 5-Aminolävulinsäure

5-Aminolevulinic acid (5-ALA) is an amino acid belonging to the group of ketocarboxylic acids.

Use

In neurosurgery, 5-ALA is used in tumor surgery and is available as a medication under the name Gliolan. In certain tumor types, such as Glioblastomas, it accumulates intracellularly and is converted there to protoporphyrin IX, enabling better intraoperative delineation of the tumor margin from the adjacent brain tissue and thereby facilitating tumor resection[^1].

5-ALA Brain Tumor — The upper image (a) shows a normal intraoperative view during glioma surgery. When the surgical field is illuminated with blue light (b) in this patient pretreated with 5-ALA, a reddish fluorescence signal is induced, making the tumor margins visible as a reddish signal. Figure adapted from Manrique-Guzmán S. et al., in: Glioblastoma (2017).

5-ALA Stummer — Progression-free survival according to Stummer et al.

5-ALA-positive tissue from a high-grade glioma after an open biopsy.

Brain metastases

Intracranial metastases may also appear 5-ALA-positive intraoperatively. In a study of 52 patients with brain metastases, 62 % were 5-ALA-positive[^2].

CNS lymphomas

CNS lymphomas may also appear 5-ALA-positive intraoperatively[^3].

Prescribing information

Detailed information on the use of Gliolan can be found in the Prescribing Information.