In addition to its effects on the adrenergic system, there is evidence that indicates that propranolol may act as a weak antagonist of certain serotonin receptors, namely the 5-HT1A, 5-HT1B, and 5-HT2B receptors. The latter may be involved in the effectiveness of propranolol in the treatment of migraine at high doses.Both enantiomers of propranolol have a local anesthetic (topical) effect, which is normally mediated by blockade of voltage-gated sodium channels. Studies have demonstrated propranolols ability to block cardiac, neuronal, and skeletal voltage-gated sodium channels, accounting for its known membrane stabilizing effect and antiarrhythmic and other central nervous system effects. Mechanism of action
Propranolol is a non-selective beta receptor antagonist. This means that it does not have preference to Beta-1 or Beta-2 receptors. It competes with sympathomimetic neurotransmitters for binding to receptors, which inhibits sympathetic stimulation of the heart. Blockage of neurotransmitter binding to beta 1 receptors on cardiac myocytes inhibits activation of adenylate cyclase, which in turn inhibits cAMP synthesis leading to reduced PKA(Protein Kinase A) activation. This results in less calcium influx to cardiac myocytes through voltage gated L-type calcium channels meaning there is a decreased sympathetic effect on cardiac cells, resulting in antihypertensive effects including reduced heart rate and lower arterial blood pressure. Blockage of neurotransmitter binding to B2 receptors on smooth muscle cells will increase contraction, which will increase hypertension. Pharmacokinetics
Propranolol is rapidly and completely absorbed, with peak plasma levels achieved about 1–3 hours after ingestion. More than 90% of the drug is found bound to plasma protein in the blood.
Umbilical-urachal sinus  is a congenital disorder of the urinary bladder caused by failure of obliteration of proximal or distal part of the allantois, and the presentation of this anomaly is more common in children and rarer in adults.It is thought have been first described by Cabriolus in 1550. Complications
Infection, with possible abscess formation. Concurrent occurrence of a tumour. See also
Urachus


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