Department of Pharmacology & Toxicology
Medical Faculty, Medical University – Sofia
Dr. Rumen Nikolov, PhD
SEMISOLID DOSAGE FORMS
AEROSOLS
PRESCRIPTION WRITING
Vehicles (bases)
A vehicle is defined as the inert carrier of
the active ingredient
Lipophilic base: paraffin oil, petroleum
jelly, wool fat (lanolin)
A lipophilic drug moves more readily into
the epidermis if it is in an aqueous vehicle
(to which it is less tightly bound)
The main rule of the local
therapy is: if the skin is dry, use an
ointment; if it is wet, use a cream.
Dry, chronic inflammation often
improves more with drugs
administered in lipophilic vehicles,
whereas moist acute inflammation
is best treated with aqueous
preparations.
Semisolid dosage forms:
Ointment (unguentum - ung.)
Paste (pasta)
Cream (creme)
Gel (gel)
Adhesive plaster (emplastrum)
Transdermal therapeutic
systems – TTS
Suppositories (suppositoria - supp.)
Ointments
Ointments are greases with the permissible
addition of up to 25% of powder by weight.
According the place of application they are:
1) unguentum dermaticum
2) unguentum ophthalmicum
3) unguentum nasale
Ointments are useful in any condition
characterized by dry skin (e.g. atopic dermatitis).
Pastes
Pastes are greases containing more
than 25% powder by weight
They are useful for dry surfaces
Pastes are very difficult to remove
19. OINTMENTS
19. A) Prescribe 2,5 g Nemybacin in
the form of eye ointment.
Rp/ Ung. ophth. Nemybacini 2,5 g
D. tub. № 1
S. Apply in the lower conjunctival sac
of the affected eye twice daily.
19b) Prescribe 30 g ointment, containing 2 g
Salicylic acid and 4 g Benzoic acid.
Rp/ Acidi salicylici 2 g
Acidi benzoici 4 g
Vaselini albi ad 30 g
M. f. unguentum
D. S. Apply to the affected skin
twice daily.
An ointment containing Benzoic acid and Salicylic
acid in a ratio of 2:1 is calls Whitfield’s ointment.
It is used mainly in the treatment of tinea pedis.
20) Prescribe 100 g officinal paste,
containing Zinc.
Rp/ Pasta Zinci 100 g
D. S. Apply to the burned
areas once daily
Creams
These are either oil-in-water (O/W) or
water-in-oil (W/O) emulsions and contain
preservatives to prevent bacterial and
fungal growth
The commonest preservatives are
parabens
Oil-in-water emulsions rub into the skin
and are easily washed off
Water-in-oil emulsions are greasier
Gels
Gels are semi-colloids which liquefy on
contact with the skin
For use on the scalp and face gels or
lotion are acceptable
Gels are a common form for acne
preparations (e. g. Acnederm)
21. Cream and gel
21a) Prescribe Lamisil (1% 15 g) as
officinal cream.
Rp/ Creme Lamisili 1% 15 g
D. tub. №1
S. Apply to the affected skin
areas twice daily.
21b) Prescribe Troxevasin 2% 40 g as
gel
Rp/ Gel Troxevasini 2% 40 g
D. tub. № 1
S. Apply to the affected area
twice daily.
Suppositories
Rectal suppositories – they can be
produced a local (to treat haemorrhiods
and ulcerative colitis) or systemic effects
(for example anti-emetic effect)
Vaginal suppositories – they are
produced a local antimicrobial effect
(e. g. Flagyl, Canesten Gyn 3)
22. Suppositories
22a) Prescribe Paracetamol as
suppositories each of 150 mg.
Rp/ Supp. Paracetamoli 150 mg
D. scat. № 1
S. Insert 1 supp. in rectum 3 times
daily.
22. Suppositories.
22b) Prescribe Ultraproct as officinal
suppositories.
Rp/ Supp. Ultraprocti
D. scat. № 1
S. Insert 1 supp. in rectum
once daily.
Plasters
Adhesive plasters – e. g. Citoplast
Transdermal patches (TTS)
• Scopoderm TTS – 1,5 mg/72 h
• Climara TTS – 25 µg/24 h
• Nitroderm TTS – 25 mg/24 h
• Duragesic TTS – 50 mcg/h
23.) Prescribe Fentanyl TTS
50 mcg/h (10 numbers).
Rp/ Fentanyl TTS 50 mcg/h
D.t.d. № 10
S. Stick 1 plaster of the skin
once daily.
Aerosols
 Most drug are intended for inhalation
are administered by a pressurized aerosol
or, less frequently, a powder inhaler.
 Aerosols for oral inhalation
1. Metered-dose inhaler (e. g. 250 µg/puff)
2. Spacers – is a large volume chamber that is
attached to the metered-dose inhaler used
to decrease the deposition of drug in the mouth
 Nasal aerosols (e.g. Olynth, Flixonase)
 Aerosols for external application
24. Aerosols.
24a) Prescribe 100 g 0,05%
Fluticasone as an officinal nasal
aerosol.
Rp/ Flixonase nasal 0,05% 100 g
D. t. d. № 1 in flac.
S. 1-2 sprays/nostril/d.
24b) Prescribe one vial Salbutamol as an
officinal aerosol (Ventolin 0,1 mg/dose).
Rp/ Fl. Ventolini 0,1 mg/dose
D. t. d. № 1
S. One puff in the mouth.