DROPS (guttae) — the liquid dosage forms registered in small amounts (5 — 10 — 30 ml) dosed by drops.
In a form K. register water, oil, glyceric and spirit solutions of medicinal substances, tinctures, liquid extracts and other liquid dosage forms, and also mixes of liquid drugs (tinctures, liquid extracts, fragrant waters and so forth). From usual liquid dosage forms To. differ only in way of dosing. Distinguish To. for external and internal use.
Counting To. for internal use carry out pipettes (see) or different types droppers (see). Accuracy of a dosage of the medicinal substances registered in To., is defined by a number of factors since the weight and volume To. in many respects depend on specific weight, superficial - a tension and viscosity of liquids, on diameter of the outlet of droppers or thickness and a form of a welt of necks of bottles, extent of their filling, an inclination, etc. Therefore it is necessary to avoid prescription in a form K. the insoluble or leaving a sediment medicinal substances and to appoint toxic and strong agents circumspectly.
Especially high requirements are imposed to eye To. As eye To. (guttae ophthalmicae) use water and oil solutions or slicks of medicinal substances.
According to requirements of GFH eye To. shall be sterile, stable, without mechanical impurities visible with the naked eye. Osmotic pressure eye To. shall correspond to the osmotic pressure of isotonic solution of sodium chloride (0,9±0,2%). If necessary for the purpose of isotoning eye To. apply buffer solutions (borate, phosphatic), and also sodium chloride, sodium sulfate or sodium nitrate taking into account compatibility of these salts with the medicinal substances which are a part eye To. As solvents at preparation eye To. use water for injections and the sterile fatty oils applied to preparation of injection solutions. For prolongation of effect of medicinal substances to eye To. sodium-carboxymethyl cellulose, methyl cellulose and polyvinyl alcohol can be added.
See also Dosage forms .
Bibliography: Muravyev. I. A. Tekhnologiya of drugs, page 449, M., 1971.
V. K. Muratov, T. D. Semenova.