药物信息为Isoptin SR (Ranbaxy Laboratories Inc.): DESCRIPTION

ISOPTIN^® SR (verapamil hydrochloride) is a calcium ion influx inhibitor (slow channel blocker or calcium ion antagonist). ISOPTIN SR is available for oral administration as light green, capsule shaped, scored, film-coated tablets containing 240 mg verapamil hydrochloride, as light pink, oval shaped, scored, film-coated tablets containing 180 mg verapamil hydrochloride, and as light violet, oval shaped, film-coated tablets containing 120 mg verapamil hydrochloride. The tablets are designed for sustained release of the drug in the gastrointestinal tract, sustained release characteristics are not altered when the tablet is divided in half.

The structural formula of verapamil HCI is given below:

C₂₇H₃₈N₂O₄•HCl M.W. 491.08

Benzeneacetronitrile, α [3-[[2-(3, 4-dimethoxyphenyl) ethyl] methylamino] propyl]-3, 4- dimethoxy-α-(1-methylethyl) hydrochloride

Verapamil HCI is an almost white, crystalline powder, practically free of odor, with a bitter taste.

It is soluble in water, chloroform and methanol. Verapamil HCI is not chemically related to other cardioactive drugs.

In addition to verapamil HCI, the ISOPTIN SR tablet contains the following ingredients: alginate, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polyvinyl pyrrolidone, talc, and titanium dioxide. The following are the color additives per tablet strength:

Strength (mg) Color Additive(s)

120 Iron Oxide

180 Iron Oxide

240 D&C yellow #10 Lake dye, and FD&C blue #2 Lake dye