The clinical importance of lipid solubility in beta blockers

The comparative effects of three lipophilic beta blocking agents--propranolol (80 mg b.i.d.) metoprolol (200 mg/d) and oxprenolol (160 mg/d) and one hydrophilic agent, atenolol (100 mg/d), were studied in patients undergoing neurosurgery. The respective penetration of these compounds into brain tissue and CSF was measured and correlated with plasma levels. The brain concentration of the three lipophilic beta blockers was high--propranolol some 20 times and oxprenolol and metoprolol some 10 times greater than the concentration of the hydrophilic, atenolol. The clinical relevance of this may be important in reducing the severity of centrally-mediated side effects, such as hallucinations and sleeplessness, by using a beta blocker less likely to penetrate the blood/brain barrier.