TETRANDRINI DIMETHIODIDUM

Toxicity

Excessive doses can be expected to produce enhanced pharmacological effects. Overdosage may increase the risk of histamine release and cardiovascular effects, especially hypotension.

Originator

Metubine Iodide,Lilly,US,1949

The Uses of TETRANDRINI DIMETHIODIDUM

Neuromuscular blocking agent.

The Uses of TETRANDRINI DIMETHIODIDUM

Metocurine Iodide is used as Zika virus protease inhibitor.

Background

Metocurine iodide is a benzylisoquinolinium competitive nondepolarizing neuromuscular blocking agent. It is used as an anesthesia adjunct to induce skeletal muscle relaxation and to reduce the intensity of muscle contractions in convulsive therapy Metocurine iodide has a moderate risk of inducing histamine release and has some ganglion blocking activity. Metocurine iodide can be used most advantageously if muscle twitch response to peripheral nerve stimulation is monitored to assess degree of muscle relaxation. Metocurine Iodide is no longer available on the US market.

Indications

For use as an anesthesia adjunct to induce skeletal muscle relaxation and to reduce the intensity of muscle contractions in convulsive therapy.

Definition

ChEBI: Metocurine iodide is an aromatic ether.

Manufacturing Process

50 grams of crude, tarry curare as received in commerce and containing about 20% of d-tubocurarine are suspended in 400 cc of 0.5 N methanolic potassium hydroxide, and the mixture is boiled for ten minutes. The dark
own insoluble material is filtered off and the filtrate is treated with 50 cc of methyl iodide and refluxed gently for about 8 hours. An additional amount of 25 cc of methyl iodide is added to the reaction mixture and the refluxing is continued for 8 hours.
The reaction mixture is evaporated to a small volume, whereupon the dtubocurarine dimethyl ether iodide precipitates. The precipitate is filtered off and dissolved in boiling water. The hot solution is treated with a small amount of decolorizing carbon, the carbon filtered off and the filtrate cooled to about 0°C. The dimethyl ether of d-tubocurarine iodide crystallizes in white crystals which melt at about 267°-270°C with decomposition.

brand name

Metubine Iodide (Lilly).

Therapeutic Function

Muscle relaxant

General Description

Metocurine iodide, ( )-O,O -dimethylchondrocurarine diiodide (Metubine iodide),is prepared from natural crude curare by extracting the curarewith methanolic potassium hydroxide. When theextract is treated with an excess of methyl iodide, the ( )-tubocurarine is converted to the diquaternary dimethylether and crystallizes out as the iodide (see “TubocurarineChloride”). Other ethers besides the dimethyl ether havebeen made and tested. For example, the dibenzyl ether wasone third as active as tubocurarine chloride, and the diisopropylcompound had only one half the activity. For comparison,the dimethyl ether has approximately 4 times theactivity of tubocurarine chloride.
The pharmacological action of this compound is the sameas that of tubocurarine chloride, namely, a nondepolarizingcompetitive blocking effect on the motor end plate of skeletalmuscles. It is considerably more potent than d-tubocurarine,however, and has the added advantage of exerting much lesseffect on respiration. The effect on respiration is not a significantfactor in therapeutic doses. Accidental overdosage iscounteracted best by forced respiration.

Pharmacokinetics

Metocurine iodide is a benzylisoquinolinium competitive nondepolarizing neuromuscular blocking agent. Metocurine iodide has a moderate risk of inducing histamine release and has some ganglion blocking activity. Metocurine iodide can be used most advantageously if muscle twitch response to peripheral nerve stimulation is monitored to assess degree of muscle relaxation. As with other nondepolarizing neuromuscular blockers, the time to onset of paralysis decreases and the duration of maximum effect increases with increasing doses of metocurine iodide. Repeated administration of maintenance doses of metocurine iodide has no cumulative effect on the duration of neuromuscular block if recovery is allowed to begin prior to repeat dosing. Moreover, the time needed to recover from repeat doses does not change with additional doses. Repeat doses can therefore be administered at relatively regular intervals with predictable results.

Metabolism

Not Available