doxycycline 61 tients > 21 yr and those with baseline Children usually need more frequent ad- forced vital capacity > 85% may need ministration of maintenance doses.† twice-daily dosing. Adjust dosage to ideal body wt in obese patients (wt ≥ 30% above ideal wt) Interactions to avoid prolonged neuromuscular block- None reported. ade. Adjust dosage in elderly patients. doxacurium chloride Interactions Nuromax Alkaline solutions: Drug is physically in- compatible with alkaline solutions; precip- Nondepolarizing neuromuscular blocker; itate may form. skeletal muscle relaxant Antibiotics, lithium, local anesthetics, PRC: C magnesium salts, procainamide, quini- dine: May enhance neuromuscular block- Available forms ing action of doxacurium. Injection: 1 mg/ml Carbamazepine, phenytoin: May cause de- layed onset and shorter duration of neuro- Indications & dosages muscular blockade. ➤ Skeletal muscle relaxation for ET intuba- Enflurane, halothane, isoflurane: May de- tion; adjunct to general anesthesia—Adult: crease dosage needed to produce 50% Dosage highly individualized. 0.05 mg/kg suppression of response to ulnar nerve rapid IV produces adequate conditions for stimulation of doxacurium. May also pro- ET intubation in 5 min in about 90% of pa- long clinically effective duration of action tients when used as part of a thiopental- of doxacurium by up to 25%. narcotic induction technique. Lower doses may need longer delay before intubation is doxycycline calcium possible. Neuromuscular blockade at this Vibramycin dose lasts about 100 min. Child > 2 yr: Dosage is highly individualized. Initially, doxycycline hyclate 0.03 mg/kg IV given during halothane Apo-Doxy*, Doryx, Doxy-100, anesthesia produces effective blockade in Doxy-200, Doxycin*, Doxytec*, Novo- 7 min and lasts 30 min. Under same con- Doxylin*, Nu-Doxycycline*, Periostat, ditions, 0.05 mg/kg produces blockade in Vibramycin,Vibra-Tabs 4 min and lasts 45 min.† ➤ Maintenance of neuromuscular block- doxycycline monohydrate ade during long procedures—Adult, child Adoxa, Monodox, Vibramycin > 2 yr: After initial dose of 0.05 mg/kg IV, maintenance doses of 0.005 and 0.01 mg/ Tetracycline; antibiotic kg prolong neuromuscular blockade for PRC: D about 30 min and 45 min, respectively. § Adjust in immunocompromised patients ¶ Adjust in debilitated patients.