There can be variation in the licensing of
different medicines containing the same drug. Forms available
from special-order manufacturers include: oral suspension, oral
solution
Tablet
CAUTIONARY AND ADVISORY LABELS 9, 14, 21
▶Nitrofurantoin (Non-proprietary)
Nitrofurantoin 50 mg Nitrofurantoin 50mg tablets | 28 tablet P
£31.33 DT = £10.41 | 100 tablet P £28.21–£111.89
Infection
Nitrofurantoin 100 mg Nitrofurantoin 100mg tablets |
28 tablet P £12.99 DT = £8.66 | 100 tablet P £21.07–£38.14
▶Genfura (Genesis Pharmaceuticals Ltd)
Nitrofurantoin 50 mg Genfura 50mg tablets | 28 tablet P £8.00
DT = £10.41 | 100 tablet P £28.57
Nitrofurantoin 100 mg Genfura 100mg tablets | 100 tablet P
£30.36
Oral suspension
CAUTIONARY AND ADVISORY LABELS 9, 14, 21
▶Nitrofurantoin (Non-proprietary)
Nitrofurantoin 5 mg per 1 ml Nitrofurantoin 25mg/5ml oral
suspension sugar-free | 300 ml P £446.95–£603.38 DT = £525.17
Modified-release capsule
CAUTIONARY AND ADVISORY LABELS 9, 14, 21, 25
▶Macrobid (Advanz Pharma)
Nitrofurantoin 100 mg Macrobid 100mg modified-release capsules
| 14 capsule P £9.50 DT = £9.50
Capsule
CAUTIONARY AND ADVISORY LABELS 9, 14, 21
▶Nitrofurantoin (Non-proprietary)
Nitrofurantoin 50 mg Nitrofurantoin 50mg capsules |
30 capsule P £16.47 DT = £12.20
Nitrofurantoin 100 mg Nitrofurantoin 100mg capsules |
30 capsule P £10.43 DT = £10.43
Fungal infection
Antifungals, systemic use
Fungal infections
The systemic treatment of common fungal infections is
outlined below; specialist treatment is required in most
forms of systemic or disseminated fungal infections. Local
treatment is suitable for a number of fungal infections
(genital, bladder, eye, ear, oropharynx, and skin).
Aspergillosis
Aspergillosis most commonly affects the respiratory tract
but in severely immunocompromised patients, invasive
forms can affect the heart, brain, and skin. Voriconazole
p. 635 is the treatment of choice for aspergillosis; liposomal
amphotericin p. 629 is an alternative first-line treatment
when voriconazole cannot be used. Caspofungin p. 628, or
itraconazole p. 632, can be used in patients who are
refractory to, or intolerant of voriconazole and liposomal
amphotericin. Itraconazole is also used for the treatment of
chronic pulmonary aspergillosis or as an adjunct in the
treatment of allergic bronchopulmonary aspergillosis
[unlicensed indication]. Posaconazole p. 634 is licensed for
use in patients with invasive aspergillosis who are refractory
to, or intolerant of itraconazole or amphotericin.
Candidiasis
Many superficial candidal infections including infections of
the skin are treated locally; widespread or intractable
infection requires systemic antifungal treatment. Vaginal
candidiasis may be treated with locally acting antifungals or
with fluconazole p. 630 given by mouth; for resistant
organisms in adults, itraconazole can be given by mouth.
Oropharyngeal candidiasis generally responds to topical
therapy; fluconazole is given by mouth for unresponsive
infections; it is effective and is reliably absorbed.
Itraconazole may be used for infections that do not respond
to fluconazole. Topical therapy may not be adequate in
immunocompromised patients and an oral triazole
antifungal is preferred.
For invasive or disseminated candidiasis, an echinocandin
can be used. Fluconazole is an alternative for Candida
albicans infection in clinically stable patients who have not
received an azole antifungal recently. Amphotericin is an
alternative when an echinocandin or fluconazole cannot be
used, however, amphotericin should be considered for the
initial treatment of CNS candidiasis. Voriconazole can be
used for infections caused by fluconazole-resistant Candida
spp. when oral therapy is required, or in patients intolerant
of amphotericin or an echinocandin. In refractory cases,
flucytosine p. 636 can be used with intravenous
amphotericin.
Cryptococcosis
Cryptococcosis is uncommon but infection in the
immunocompromised, especially in HIV-positive patients,
can be life-threatening; cryptococcal meningitis is the most
common form of fungal meningitis. The treatment of choice
in cryptococcal meningitis is amphotericin by intravenous
infusion and flucytosine by intravenous infusion for 2 weeks,
followed by fluconazole by mouth for 8 weeks or until
cultures are negative. In cryptococcosis, fluconazole is
sometimes given alone as an alternative in HIV-positive
patients with mild, localised infections or in those who
cannot tolerate amphotericin. Following successful
treatment, fluconazole can be used for prophylaxis against
relapse until immunity recovers.
Histoplasmosis
Histoplasmosis is rare in temperate climates; it can be life-
threatening, particularly in HIV-infected persons.
Itraconazole can be used for the treatment of
immunocompetent patients with indolent non-meningeal
infection, including chronic pulmonary histoplasmosis.
Amphotericin by intravenous infusion is used for the initial
treatment of fulminant or severe infections, followed by a
course of itraconazole by mouth. Following successful
treatment, itraconazole can be used for prophylaxis against
relapse until immunity recovers.
Skin and nail infections
Mild localised fungal infections of the skin (including tinea
corporis, tinea cruris, and tinea pedis) respond to topical
therapy. Systemic therapy is appropriate if topical therapy
fails, if many areas are affected, or if the site of infection is
difficult to treat such as in infections of the nails
(onychomycosis) and of the scalp (tinea capitis). Oral
imidazole or triazole antifungals (particularly itraconazole)
and terbinafine p. 1300 are used more frequently than
griseofulvin p. 636 because they have a broader spectrum of
activity and require a shorter duration of treatment.
Tinea capitis is treated systemically; additional topical
application of an antifungal may reduce transmission.
Griseofulvin is used for tinea capitis in adults and children; it
is effective against infections caused by Trichophyton
tonsurans and Microsporum spp. Terbinafine is used for tinea
capitis caused by T. tonsurans[unlicensed indication]. The
role of terbinafine in the management of Microsporum
infections is uncertain.
Pityriasis versicolor may be treated with itraconazole by
mouth if topical therapy is ineffective; fluconazole by mouth
is an alternative. Oral terbinafine is not effective for
pityriasis versicolor.
Antifungal treatment may not be necessary in
asymptomatic patients with tinea infection of the nails. If
treatment is necessary, a systemic antifungal is more
effective than topical therapy. Terbinafine and itraconazole
have largely replaced griseofulvin for the systemic treatment
of onychomycosis, particularly of the toenail; terbinafine is
considered to be the drug of choice. Itraconazole can be
administered as intermittent ‘pulse’ therapy. Topical
antifungals also have a role in the treatment of
onychomycosis.
Immunocompromised patients
Immunocompromised patients are at particular risk of fungal
infections and may receive antifungal drugs
prophylactically; oral triazole antifungals are the drugs of
choice for prophylaxis. Fluconazole is more reliably absorbed
than itraconazole, but fluconazole is not effective against
Aspergillus spp. Itraconazole is preferred in patients at risk of
invasive aspergillosis. Posaconazole can be used for
prophylaxis in patients who are undergoing haematopoietic
stem cell transplantation or receiving chemotherapy for
acute myeloid leukaemia or myelodysplastic syndrome.
Micafungin p. 628 can be used for prophylaxis of candidiasis
in patients undergoing haematopoietic stem cell
transplantation when fluconazole, itraconazole or
posaconazole cannot be used.
Amphotericin by intravenous infusion or caspofungin is
used for the empirical treatment of serious fungal infections;
caspofungin is not effective against fungal infections of the
CNS.
Triazole antifungals
Triazole antifungal drugs have a role in the prevention and
systemic treatment of fungal infections.
Fluconazole is very well absorbed after oral
administration. It also achieves good penetration into the
cerebrospinal fluid to treat fungal meningitis. Fluconazole is
excreted largely unchanged in the urine and can be used to
treat candiduria.
Itraconazole is active against a wide range of
dermatophytes. Itraconazole capsules require an acid
environment in the stomach for optimal absorption.
Itraconazole has been associated with liver damage and
should be avoided or used with caution in patients with liver
disease; fluconazole is less frequently associated with
hepatotoxicity.
Posaconazole is licensed for the treatment of invasive
fungal infections unresponsive to conventional treatment.
Voriconazole is a broad-spectrum antifungal drug which is
licensed for use in life-threatening infections.
Imidazole antifungals
The imidazole antifungals include clotrimazole p. 875,
econazole nitrate p. 875, ketoconazole p. 718, and
tioconazole p. 1299. They are used for the local treatment of
vaginal candidiasis and for dermatophyte infections.
Miconazole p. 1283 can be used locally for oral infections; it
is also effective in intestinal infections. Systemic absorption
may follow use of miconazole oral gel p. 1283 and may result
in significant drug interactions.
Polyene antifungals
The polyene antifungals include amphotericin p. 629 and
nystatin p. 1284; neither drug is absorbed when given by
mouth. Nystatin is used for oral, oropharyngeal, and perioral
infections by local application in the mouth. Nystatin is also
used for Candida albicans infection of the skin.
Amphotericin by intravenous infusion is used for the
treatment of systemic fungal infections and is active against
most fungi and yeasts. It is highly protein bound and
penetrates poorly into body fluids and tissues. When given
parenterally amphotericin is toxic and side-effects are
common. Lipid formulations of amphotericin (Abelcet ® and
AmBisome ®) are significantly less toxic and are
recommended when the conventional formulation of
amphotericin is contra-indicated because of toxicity,
especially nephrotoxicity or when response to conventional
amphotericin is inadequate; lipid formulations are more
expensive.
Echinocandin antifungals
The echinocandin antifungals include anidulafungin below,
caspofungin p. 628 and micafungin p. 628. They are only
active against Aspergillus spp. and Candida spp.; however,
anidulafungin and micafungin are not used for the treatment
of aspergillosis. Echinocandins are not effective against
fungal infections of the CNS.
Other antifungals
Flucytosine p. 636 is used with amphotericin in a synergistic
combination. Bone marrow depression can occur which
Infection
limits its use, particularly in HIV-positive patients; weekly
blood counts are necessary during prolonged therapy.
Resistance to flucytosine can develop during therapy and
sensitivity testing is essential before and during treatment.
Flucytosine has a role in the treatment of systemic
candidiasis and cryptococcal meningitis.
Griseofulvin p. 636 is effective for widespread or
intractable dermatophyte infections but has been
superseded by newer antifungals, particularly for nail
infections. It is the drug of choice for trichophyton infections
in children. Duration of therapy is dependent on the site of
the infection and may extend to a number of months.
Terbinafine p. 1300 is the drug of choice for fungal nail
infections and is also used for ringworm infections where
oral treatment is considered appropriate.
ANTIFUNGALS › ECHINOCANDIN ANTIFUNGALS
PDF pages 648, 649
