WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
Skin Irritation
The skin of certain individuals may become dry, red, or
exfoliated while using Atralin Gel. If the degree of irritation warrants,
patients should be directed to temporarily reduce the amount or frequency of
application of the medication, discontinue use temporarily, or discontinue use
all together. Efficacy at reduced frequencies of application has not been
established. If a reaction suggesting sensitivity occurs, use of the medication
should be discontinued. Mild to moderate skin dryness may also be experienced;
if so, use of an appropriate moisturizer during the day may be helpful.
Tretinoin has been reported to cause severe irritation on
eczematous or sunburned skin and should be used with caution in patients with
these conditions.
To help limit skin irritation, patients must:
- wash the treated skin gently, using a mild, non-medicated
soap, and pat it dry
- avoid washing the treated skin too often and scrubbing
the affected skin area
- avoid contact with the peels of limes
Ultraviolet Light And Environmental Exposure
Unprotected exposure to sunlight, including sunlamps,
should be minimized during the use of Atralin Gel. Patients who normally
experience high levels of sun exposure, and those with inherent sensitivity to
sun, should be warned to exercise caution. Use of sunscreen products of at
least SPF 15 and protective clothing over treated areas is recommended when
exposer cannot be avoided.
Weather extremes, such as wind or cold, also may be irritating
to tretinoin-treated skin.
Fish Allergies
Atralin Gel contains soluble fish proteins and should be
used with caution in patients with known sensitivity or allergy to fish.
Patients who develop pruritus or urticaria should contact their health care
provider.
Patient Counseling Information
See FDA-Approved Patient Labeling (PATIENT INFORMATION)
Instruct patients to clean the affected areas with an
appropriate cleanser before applying Atralin Gel.
Patients may use moisturizers that are non-comedogenic,
and should avoid products that could be drying or irritating.
Patients may also wear cosmetics while being treated with
Atralin Gel; however, they should be instructed to remove the cosmetics and clean
the area thoroughly before applying Atralin Gel.
Warn patients of the drying and irritation effects often
seen during treatment. Continue use of the medication if these effects are
tolerable.
Caution patients against application of Atralin Gel
around the eyes, mouth, paranasal creases, and mucous membranes as the skin is
especially prone to irritation.
Minimize exposure to sunlight, including sunlamps.
Recommend the use of sunscreen products and protective apparel (e.g., hat) when
exposure cannot be avoided.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
A 2-year dermal mouse
carcinogenicity study was initiated with topical administration of 0.005%,
0.025% and 0.05% Atralin Gel. Although no drug-related tumors were observed in
surviving animals, the irritating nature of the drug product precluded daily dosing,
confounding data interpretation and reducing the biological significance of
these results.
Studies in hairless albino mice
with a different formulation suggest that concurrent exposure to tretinoin may
enhance the tumorigenic potential of carcinogenic doses of UVB and UVA light
from a solar simulator. This effect was confirmed in a later study in pigmented
mice, and dark pigmentation did not overcome the enhancement of
photocarcinogenesis by 0.05% tretinoin. Although the significance of these
studies to humans is not clear, patients should minimize exposure to sunlight
or artificial ultraviolet irradiation sources.
The genotoxic potential of
tretinoin was evaluated in an in vitro bacterial reversion test, an in vitro chromosomal
aberration assay in human lymphocytes and an in vivo rat micronucleus assay.
All tests were negative. In dermal fertility studies of another tretinoin
formulation in rats, slight (not statistically significant) decreases in sperm
count and motility were seen at 0.5 mg/kg/day (3 mg/m²,
approximately 4 times the clinical dose based on body surface area comparison),
and slight (not statistically significant) increases in the number and percent
of nonviable embryos in females treated with 0.25 mg/kg/day and above (1.5 mg/m²,
approximately 2 times the clinical dose based on body surface area comparison),
were observed.
Use In Specific Populations
Pregnancy
Pregnancy Category C
There are no well-controlled trials in pregnant women
treated with Atralin Gel. Atralin Gel should be used during pregnancy only if
the potential benefit justifies the potential risk to the fetus.
Atralin Gel at doses of 0.1, 0.3 and 1 g/kg/day was
tested for maternal and developmental toxicity in pregnant Sprague-Dawley rats
by dermal application. The dose of 1 g/kg/day was approximately 4 times the
clinical dose assuming 100% absorption and based on body surface area
comparison. Possible tretinoin-associated teratogenic effects (craniofacial
abnormalities (hydrocephaly), asymmetrical thyroids, variations in ossification,
and increased supernumerary ribs) were noted in the fetuses of Atralin Gel
treated animals. These finding were not observed in control animals. Other
maternal and reproductive parameters in the Atralin Gel treated animals were
not different from control. For purposes of comparison of the animal exposure
to human exposure, the clinical dose is defined as 2 g of Atralin Gel applied
daily to a 50 kg person.
Oral tretinoin has been shown to be teratogenic in rats,
mice, rabbits, hamsters and nonhuman primates. Tretinoin was teratogenic in
Wistar rats when given orally in doses greater than 1 mg/kg/day (approximately
8 times the clinical dose based on body surface area comparison). In the
cynomolgus monkey, fetal malformations were reported for doses of 10 mg/kg/day,
but none were observed at 5 mg/kg/day (approximately 80 times the clinical dose
based on body surface area comparison), although increased skeletal variations
were observed at all doses. Dose-related increases in embryolethality and
abortion also were reported. Similar results have also been reported in pigtail
macaques.
Topical tretinoin in a different formulation has
generated equivocal results in animal teratogenicity tests. There is evidence
for teratogenicity (shortened or kinked tail) of topical tretinoin in Wistar
rats at doses greater than 1 mg/kg/day (approximately 8 times the clinical dose
assuming 100% absorption and based on body surface area comparison). Anomalies
(humerus: short 13%, bent 6%, os parietal incompletely ossified 14%) have also
been reported when 10 mg/kg/day (approximately 160 times the clinical dose
assuming 100% absorption and based on body surface areas comparison) was
topically applied. Supernumerary ribs have been a consistent finding in rats
when dams were treated topically or orally with retinoids.
With widespread use of any drug, a small number of birth
defect reports associated temporally with the administration of the drug would
be expected by chance alone. Cases of temporally associated congenital
malformations have been reported with use of other topical tretinoin products.
The significance of these spontaneous reports in terms of risk to the fetus is
not known.
Nonteratogenic effects on fetuses
Oral tretinoin has been shown to be fetotoxic in rats
when administered in doses 20 times the clinical dose based on body surface
area comparison. Topical tretinoin has been shown to be fetotoxic in rabbits
when administered in doses 8 times the clinical dose based on body surface area
comparison.
Nursing Mothers
It is not known whether this drug is excreted in human
milk. Because many drugs are excreted in human milk, caution should be
exercised when Atralin Gel is administered to a nursing woman.
Pediatric Use
Safety and effectiveness in children below the age of 10
have not been established.
A total of 381 pediatric subjects (aged 10 to 16 years)
treated with Atralin Gel were enrolled into the two clinical studies. Across
these two studies, comparable safety and efficacy were observed between
pediatric and adult subjects.
Geriatric Use
Safety and effectiveness in a geriatric population have
not been established. Clinical studies of Atralin Gel did not include any
subjects over age 65 to determine whether they respond differently from younger
subjects.