Examples
Allylamines
| Generic Name | Brand Name |
| terbinafine hydrochloride |
Lamisil tablets
|
Azoles
| Generic Name | Brand Name |
| fluconazole |
Diflucan
|
| itraconazole |
Sporanox
|
| ketoconazole |
Nizoral
|
Other oral antifungals
| Generic Name | Brand Name |
| griseofulvin |
Grifulvin V
|
All of these medicines are by
prescription only. Allylamines and azoles are classes of drugs. Their
effectiveness and side effects may vary.
Terbinafine tablets are
taken once a day for 6 weeks for fungal fingernail infections, and for 12 weeks
or longer for fungal toenail infections. Terbinafine tablets can be used
according to a pulse dosing schedule. Pulse dosing refers to taking medicine
daily for 1 week a month for 2, 3, or 4 months. Some people find it easier to
stay with this medication schedule, and the treatment is likely to be
cheaper.
Oral azoles (tablets or capsules) are taken daily for 3
to 18 months, depending on the medicine. Oral azoles can be used according to a
weekly pulse dosing schedule. Pulse dosing refers to taking medicine daily for
1 week a month for 2, 3, or 4 months. Some people find it easier to stay with
this medication schedule, and the treatment is likely to be cheaper.
Griseofulvin is taken twice a day until nails are clear of infection. For
infections in the fingernails, griseofulvin may be taken for 6 to 8 months. For
infections in toenails, griseofulvin may be taken for 12 to 18 months to cure
an infection and to prevent reinfection.
How It Works
Allylamines and azoles kill
fungi. Griseofulvin prevents the growth of fungi.
Killing fungi does not guarantee a normal-looking nail.
Why It Is Used
Oral antifungal medicines are used
to treat
fungal nail infections. Often the medicine used
depends on the
type of infection you have.
- Terbinafine is a first-line medication for fungal nail infections
caused by dermatophytes, including
distal subungual onychomycosis
and white superficial onychomycosis.1 Most fungal nail infections are caused by this type of
fungus. Terbinafine may also be effective against some molds
(nondermatophytes).
- Itraconazole is a preferred medicine for infections caused by
molds and yeast (Candida).1 It
can also be used for dermatophytes.
- Fluconazole is a first-line medication for Candida infections and can also be used against
dermatophytes.1 It may be used if you are taking a lot
of other medicines.1
- Griseofulvin is more effective against fingernail infections than
toenail infections and is rarely used for toenail infections. It is only
effective against infections caused by dermatophytes. It is the only antifungal
currently approved by the U.S. Food and Drug Administration (FDA) for fungal
nail infections in children.
How Well It Works
Oral antifungals may cure fungal
nail infections. Most research has been on using these medicines for toenail
infections.
Research on oral terbinafine
reports that in people with a fungal nail infection caused by dermatophytes,
it:2
- Killed fungi in 40% to 90% of the people using it.
- Produced a normal-looking nail in 35% to 50% of the people using
it.
- Was more effective than itraconazole, griseofulvin, or
fluconazole.
Research on other oral antifungals
reports that:
- Fluconazole improved the appearance of more than 75% of a toenail
in 72% to 89% of people using it.1 When taken in high
doses once a week for 3 months for fingernail infection, oral fluconazole
produced a normal-looking fingernail in 90% of people using it and killed the
fungi in nearly all the people using it.1
- Itraconazole killed fungi in 45% to 70% of people using it and
produced a normal-looking nail in 35% to 80% of the people using it.1
- Griseofulvin has low cure rates and is not considered standard
treatment for fungal toenail infections.3
Oral antifungal medicines often kill fungi but do not
immediately improve the appearance of the nail.
Side Effects
Oral antifungals have both minor and
dangerous side effects.
Minor side effects include:
- Headaches.
- Stomach upset.
- Skin rashes.
- Changes in taste sensation (rare, and with terbinafine
only).
- Visual disturbances (rare, and with terbinafine only).
- Increased sensitivity of skin to sunlight (photosensitivity—with
griseofulvin only).
Dangerous side effects of oral antifungals include:4
- Drug interactions. Commonly prescribed medicines can increase or
decrease terbinafine or azole levels in your body. Similarly, other medicines
can build up in the bloodstream when taken with terbinafine or an azole. Before
you take oral antifungal medicines, let your doctor know what other medicines
you are taking.
-
Liver damage or failure, requiring a liver transplant.
A small number of deaths after liver failure have been linked to terbinafine
and azoles. Warning signs of liver failure include:
- Nausea, vomiting, abdominal pain.
- Fatigue.
- Loss of appetite.
- Dark urine.
- Changes in skin color.
Itraconazole may cause
heart failure. Warning signs of heart failure
include:
- Shortness of breath at rest, with mild exertion, or when lying
flat.
- Severe swelling of feet, ankles, legs, or abdomen.
- Weight gain.
- Fatigue.
- Coughing up white or pink mucus.
- Faster-than-usual heart rate.
During oral antifungal treatment, your doctor may require
blood tests to check your kidney and liver function.
See Drug
Reference for a full list of side effects. (Drug Reference is not available in
all systems.)
What To Think About
Terbinafine and azoles pass into
breast milk; it is not known whether they harm a fetus. It is not known whether
griseofulvin passes into breast milk. If you are pregnant, could become
pregnant, or are breast-feeding, talk to your doctor before taking oral
antifungal medicines.
Advanced age decreases your chances of a
cure. A study of oral antifungals in people older than 60 reported fungal
infection cure rates of about 64%. This lower-than-average cure rate may be due
to slowed nail growth and, in some people, poor blood circulation to the
feet.5
Griseofulvin was one of the first
oral antifungal medicines. But it does not provide a long-term cure, has
serious side effects, and requires a long treatment time (12 to 18 months). The
newer oral antifungals are much more effective, relatively safe for healthy
people, and don't take as long to work.
Oral azoles are best
absorbed into the body when taken with cola, orange juice, or food. Some
medicines may decrease your body's absorption of azole medication. These
include cimetidine (Tagamet), stomach acid neutralizers, and rifampin
(Rifadin).
Griseofulvin should be taken with fatty foods for
better absorption into the body.
Some people redevelop a fungal
infection (recurrence) after treatment. Recurrence of infection may be a new
infection or a regrowth of the original infection that was not eliminated by
treatment.
Consider the following about treatment with oral
antifungal medicine:
- Oral antifungal medicines are not recommended if you have liver
problems.
- Do not drink alcohol while taking these medicines, as this
increases your risk of liver damage.
- Itraconazole (Sporanox) is not recommended if you have a history
of
heart failure.
- Griseofulvin should not be taken if you have
lupus or are allergic to penicillin.
For more information on deciding whether to use oral
antifungal medicines, see:
-
Should I take oral antifungal medicine to treat a fungal nail infection?
Complete the new medication information form (PDF)
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