Premedication antimuscarinics

Hyoscine - premedication antimuscarinic to inhibit gastric secretion and intestinal motility prior to gastrointestinal imaging Ibuprofen - non-steroidal anti-inflammatory dmg Imipramine - antidepressant Indinavir - antiviral HIV... 

Four main groups of drugs are used as premedication and as adjuncts to general anaesthesia sedatives antimuscarinic drugs muscle relaxants and analgesics. Table 12.2 shows actions and examples of drugs used to supplement general anaesthesia. 

Antimuscarinic drugs are used as premedication to prevent salivation and bronchial secretions during an operation and to protect the heart from arrhythmias caused by inhalation anaesthetics such as halothane and propofol. They are less commonly used nowadays because modern anaesthetics are less irritant. 

The inhalational anaesthetics increase the effects of the neuromuscular blockers to differing extents, but nitrous oxide appears not to interact significantly. Ketamine has been reported to potentiate the effects of atracurium. Propofol does not appear to interact with mivacurium or vecuronium. Xenon is reported not to interact with mivacurium or rocuronium, and has less effect than sevoflurane on vecuronium neuromuscular blockade. Bradycardia has been seen in patients given vecuronium with eto-midate or thiopental. Propofol can cause serious bradycardia if it is given with suxamethonium (succinylcholine) without adequate antimuscarinic premedication, and asystole has been seen when fentanyl, propofol and suxamethonium were given sequentially. 

---