Liquid dosage forms

Simple and complex solutions

Solutions (Solutiones) are a basic liquid dosage form. They can be aqueous, alcoholic, and oily. In a Latin prescription, the word "solution" is always placed in the genitive singular — Solutionis. When prescribing a medication, it is extremely important to indicate the nature of the solvent if it is not ordinary purified water.

For example, to prescribe an alcoholic solution of hydrogen peroxide, the prescription begins by indicating the form and concentration: Take of alcoholic solution of hydrogen peroxide 1.5% 50 ml. In Latin, this is written as follows: Rp.: Solutionis Hydrogenii peroxydi spirituosae 1.5% — 50 ml. At the end, the standard abbreviation D.S. is added, which stands for Da. Signa. (Dispense. Label).

If oil is used as a solvent, the adjective oleosa is added to the name. A classic example of an oily solution for external use is camphor oil solution: Solutio Camphorae oleosa. If a physician prescribes a 10% solution with a volume of 10 ml, it is intended exclusively for external use.

Solution mixtures and mixtures

In medical practice, it is often necessary to mix several liquids in one vial. If absolutely identical quantities of different components are taken, the term ana (of each, in equal parts) is used. For example, when prescribing a mixture of 10% norsulfazole-sodium solution and isotonic sodium chloride solution 10 ml each, the entry looks like this:

• Rp.: Solutionis Norsulfazoli-natrii 10 %
• Solutionis Natrii chloridi isotonicae ana 10 ml

Following the list of ingredients is the instruction M.D.S., which means Misce. Da. Signa. (Mix. Dispense. Label).

A separate extensive category consists of mixtures (mixturae). A mixture is a combination of various liquid forms. As a clear example, we can consider a mixture of a herbal infusion and syrup. To prepare such a mixture, marshmallow root infusion (Infusum radicis Althaeae) is taken, which is prepared at the rate of 3.0 grams of dry raw material per 100 ml of finished infusion. 20 ml of marshmallow syrup (Sirupus Althaeae) is added to this base volume. The instruction to the pharmacist in this case comes down to simple and clear commands: Mix. Dispense.

Liquid forms for injection and ampoules

Liquid dosed dosage forms are very often manufactured in factory ampoules. For example, the drug deoxycorticosterone (belonging to the mineralocorticoid group) in the form of acetate is used as a ready-made oil solution (Solutio oleosa). For intramuscular administration, a concentration of 0.5% with a volume of 1 ml in the amount of 10 ampoules is prescribed.

Formatting the prescription for this drug requires a precise indication of the form: > Rp.: Solutionis Desoxycorticosteroni acetatis oleosae 0.5% — 1 ml

This is followed by the mandatory instruction to dispense such doses in the quantity of 10 in ampoules: D.t.d. N. 10 in ampullis (Da tales doses numero — Give such doses in this number).

Special attention should be paid to prescriptions for injection solutions that are prepared and mixed directly in the pharmacy compounding department. In such situations, it is absolutely necessary to demand sterilization. For example, when mixing 2.5% chlorpromazine solution 2 ml and 5% glucose solution 20 ml (Solutionis Aminazini, Solutionis Glucosi), the prescription must end with the strict command: Misce. Sterilisa! Da. (Mix. Sterilize! Dispense).

Drops and complex combined formulations

The liquid dosage form in the form of drops can include tinctures, various alcoholic solutions, and a complex of oils. A relatively simple option for drops with the addition of menthol and eucalyptus is prescribed as follows: 0.15 grams of crystalline menthol (Mentholi 0,15) and 50 ml of eucalyptus tincture (Tincturae Eucalypti 50 ml) are taken. At the end, the command to mix, dispense, and label is placed — M.D.S.

More complex drops are a multicomponent combined solution. Such drops may simultaneously include:

1. Alcoholic solution of furatsilin (Solutio Furacilini spirituosa) 0.1% in a volume of 2 ml.
2. Dry substance menthol (Mentholum) with a mass of 0.06 grams.
3. Eucalyptus oil (Oleum Eucalypti).
4. Castor oil (Oleum Ricini).
5. Olive oil (Oleum Olivarum).

If olive oil is used as a base to bring the total volume of the liquid to the required value (for example, exactly up to 15 ml), the special preposition ad is used in the prescription line: ad 15 ml. After a detailed list of all active and auxiliary components, the pharmacist is instructed to mix them and dispense the finished drug to the patient.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Rules for prescribing herbal infusions (Infusum)
• Features of the formulation of alcoholic solutions (Solutiones spirituosae)
• Combinations of oils (oleosa) for external use
• Specifics of prescribing complex mixtures with syrups
• Use of isotonic sodium chloride solution as a solvent

Other topics in the section "Termino-element Vocabulary (from meaning to TE)"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.