LIQUID DOSAGE FORM

1. Department of Pharmacology & Toxicology
Medical Faculty, Medical University – Sofia
Dr. Rumen Nikolov, PhD
Liquid
dosage forms

2. Liquid dosage forms are prepared:
(1) by dissolving the active drug
substance(s) in an aqueous or
nonaqueous (e.g. alcohol, ether,
glycerin) solvent, (2) by suspensing
the drug in appropriate medium, or
(3) by incorporating the drug
substance into an oil or water
phases.

3. Liquid dosage forms can be
administered:
• Topically - lotions or
suspension applied to the skin, eye drops,
nasal drops, ear drops
• Orally (p.o.) - oral
suspension and solution
• Parenterally -
subcutaneous injection (s.c.),
intramuscular injection (i.m.)
and intravenous administration (i.v.)

4. Solution (solutio)
•Solutions are prepared by
dissolving a solid or liquid drug
in distilled water (aqua destillata)
•Solutions are intended for
topical, oral, and parenteral
administration. Solutions for
local administration usually
called lotions.

5. Suspension (suspensio)
•A suspension consists of a
dispersion of relatively coarse
particles, usually in aqueous vehicle.
•Suspensions may be used for
oral and topical administration.
•Like solutions, oral suspensions are
useful in children and patients who
cannot tolerate a solid dosage form.

6. Drops (guttae)
•Drops are solutions, tinctures
or mixtures of high-potent
drug substances
•Drops are prescribed in small
quantity (10−30 g)

7. •Drops are intended to be
administered orally or externally
(as eye drops, nasal drops and
ear drops).
•eye drops (collyrium): Timolol
•nasal (nose) drops: Olynth 0,1%
•ear drops: Furotalgin

8. Emulsion (emulsio)
Emulsions are two-phase
systems consist of liquid drug
substances.
 They are classfied as:
• oil-in-water emulsion (O/W)
• water- in-oil emulsion (W/O)
 Emulsions can be administered
topically, orally, and I.M.

9. Liniment (linimentum)
•Liniments are milk-like liquids
for topical administration.
•Example:
 Carmolis fluid
 Nival

10. Infusions and decoctions
• Infusion (infusum) is a dilute
solution of the readily soluble
constituents of crude drugs (from
the soft parts of plants).
• Fresh infusions are prepared by
macerating the drugs for a short
period of time (15 min) with
boiling water.

11. Decoction (decoctum)
• Decoctions is an extract of the
water-soluble and heat-stable
constituents of crude drugs (from
the hard parts of plants) by boiling
in water for 30 min, and cooling.
• Infusions and decoctions are of
short duration (no more than 3
days).

12. Mixture (mixtura)
Mixtures contain two or more
active drug substance, dissolved,
suspensed, or dispersed in a
suitable liquid base.
Syrups are added as remedium
corrigens, in quantity of 20 % or
30 % of the total volume.
Oral and topical administration

13. Medical nail lacquers
•Such dosage form contains
antifungal drugs for topical
treatment of onychomycosis
•Example:
Batrafen nail lacquer 8 %
Loceryl nail lacquer 8 %

14. Medical shampoo
Selected topical formulations
for the treatment of seborrheic
dermatitis are:
•Nizoral shampoo
•Selsun shampoo

15. Sterile dosage forms for injection
These forms contain solutions,
powder or lyophilized powder
ready to be dissolve, suspensions,
and emulsions. They are packaged
in ampoules, vials, plastic bags,
one-point cut ampoules, and
prefilled disposable syringes.

16. 10.a) Solutions can be prescribed in
two forms (short or enlarged).
•in short form the strength of a solution
is expressed as the quantity of solute in
sufficient solvent to make 100 ml
(percentage strength)
Rp/ Sol. Natrii citratis 4% 150 g
D.S. Take 1 tablespoon 3
times daily.

17. •in enlarged form the total dose of
the active substance, the name of
the solvent, and the total volume of
the solution are filled in praescriptio
Rp/ Natrii citratis 6 g
Aquae destillatae ad 150 g
M.D.S. Take 1 tablespoon
3 times daily.
M.D.S. = Misce. Da. Signa.

18. 10.b)
Rp/ Sol. Iodi spirituosae 5% 100 g
D.S. For external use.
11.)
Rp./Fl. Tussiroli 140 ml
D. t .d. №1
S. Take 1 teaspoon
3 times daily.
D.t.d. = Da tales doses

19. 12.)
Rp/ Infusi radicis Primulae 6 g/180 g
Ephedrini hydrochloridi 300 mg
Liquoris Ammonii anisati 3 g
Natrii benzoatis 3 g
Sirupi Althaeae ad 225 g
M. f. mixtura
D.S. Take 1 tablespoon
3 times daily.

20. 12.) Calculation of the total dose
of each drug of the mixture:
•one tablespoon contains 15 ml (g)
•the total number of doses is equal
to the whole volume of mixture divided
by the volume of the one tablespoon:
225 g : 15 = 15
•the total dose of each drug substance
is equal to the total number of doses
multiplied by the single dose of the drug

21. 12.)
•Ephedrini hydrochloridi
single dose = 20 mg
total dose = 15 x 20 mg = 300 mg
•Liquoris Ammonii anisati
single dose = 200 mg
total dose = 15 x 200 mg = 3 g
•Natrii benzoatis
single dose = 200 mg
total dose = 15 x 200 mg = 3 g

22. 13a) Tinctura (T-ra)
Rp/ T-ra Valerianae 20 g
D.S. Take 20 drops 3 times
daily.

23. 13.b) Drops
Rp/ Fl. Xylomethazolini 0,1% 10 ml
D. t. d. №1
S. Put 2 drops into nose 4 times
daily.

24. 14.) Suspensions
Rp/ Fl. Cefuroxime 25 mg/5 ml
D. t. d. № 1
S. Take 2 ml every 12 hours.

25. 14.) Calculation of the single dose
of Cefuroxime axetil for a child
with body weight 10 kg:
-- Daily dose = 10 mg x 10 kg = 100 mg
-- The daily dose is divided by 2 equal
applications: 100 mg/2 = 50 mg
-- One ml (or 1 division) of suspension
contains 25 mg of Cefuroxime or
single dose = 100 mg/2 mg = 2 ml

26. 15.) Infusions and decoctions
Rp/ Decocti fol. Uvae ursi 10 g/200 g
D. S. Take 1 tablespoon
3 times daily.

27. 16)
Rp/ Sol. Lydoli 5% 2 ml
D. t. d. № 10 in amp.
S. One ampule S.C.
Pethidine – INN (Lydol®
)
(Meperidine - USA)

28. 17)
Rp/ Fl. Benzylpenicillini 500 000 UI
D. t. d. № 20
S. One vial I.M. every 6 hours,
after dissolving in 5 ml distilled
water.

29. 18a)
Rp/ Fl. Fentanyli 0,005% 10 ml
D. t. d. № 1
S. Injected 2 ml I.M.
18b)
Rp/ Fl. Droperidoli 0,25% 10 ml
D. t. d. № 1
S. Injected 2 ml I.M.