Page 56 - phytochemistry general program

Pharmacological action and uses

The pharmacological activity of opium is due to the alkaloid morphine which acts
first as stimulating then depressant to the central nervous system and respiratory

centers.

Opium is not as effective as morphine because of its slower absorption, but .1
it has a greater constipating action and is thus better used in antidiarrheal

preparations :Tincture opii camphorata (Elixir paregoric).

Opium also exerts a valuable expectorant action (Dover’s powder) .2

Morphine: powerful analgesic drug.(pain-killer) .3

Codeine: is much weaker in action than morphine, development of tolerance .4
and addiction is less. It is mainly used to relief dry initiating cough.

Papaverine: is chiefly used as smooth muscle relaxant especially in .5
bronchial asthma, arterial spasm and intestinal colic.

Narcotine: is effective cough sedative, .6

Apomorphine: has little depressant action on CNS, but is an effective as .7
emetic, expectorant and aphrodisiac.

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