PRECAUTIONS
Acute Abdominal Conditions
The administration of RYBIX ODT may complicate the
clinical assessment of patients with acute abdominal conditions.
Use In Renal And Hepatic Disease
Impaired renal function results in a decreased rate and
extent of excretion of tramadol and its active metabolite, M1. In patients with
creatinine clearances of less than 30 mL/min, dosing reduction is recommended
(see DOSAGE AND ADMINISTRATION). Metabolism of tramadol and M1 is
reduced in patients with advanced cirrhosis of the liver. In cirrhotic
patients, dosing reduction is recommended (see DOSAGE AND ADMINISTRATION).
With the prolonged half-life in these conditions, achievement
of steady-state is delayed, so that it may take several days for elevated
plasma concentrations to develop.
Carcinogenesis, Mutagenesis, Impairment Of Fertility
A slight, but statistically significant, increase in two
common murine tumors, pulmonary and hepatic, was observed in a mouse
carcinogenicity study, particularly in aged mice. Mice were dosed orally up to
30 mg/kg (90 mg/m² or 0.36 times the maximum daily human dosage of 246 mg/m²)
for approximately two years, although the study was not done with the Maximum
Tolerated Dose. This finding is not believed to suggest risk in humans. No such
finding occurred in a rat carcinogenicity study (dosing orally up to 30 mg/kg,
180 mg/m², or 0.73 times the maximum daily human dosage).
Tramadol was not mutagenic in the following assays: Ames
Salmonella microsomal activation test, CHO/HPRT mammalian cell assay, mouse
lymphoma assay (in the absence of metabolic activation), dominant lethal
mutation tests in mice, chromosome aberration test in Chinese hamsters, and bone
marrow micronucleus tests in mice and Chinese hamsters. Weakly mutagenic
results occurred in the presence of metabolic activation in the mouse lymphoma
assay and micronucleus test in rats. Overall, the weight of evidence from these
tests indicates that tramadol does not pose a genotoxic risk to humans.
No effects on fertility were observed for tramadol at
oral dose levels up to 50 mg/kg (300 mg/m²) in male rats and 75 mg/kg (450 mg/m²)
in female rats. These dosages are 1.2 and 1.8 times the maximum daily human
dosage of 246 mg/m², respectively.
Pregnancy
Teratogenic Effects
Pregnancy Category C. Tramadol has been shown to be
embryotoxic and fetotoxic in mice, (120 mg/kg or 360 mg/m²), rats (≥ 25
mg/kg or 150 mg/m²) and rabbits (≥ 75 mg/kg or 900 mg/m²) at maternally
toxic dosages, but was not teratogenic at these dose levels. These dosages on a
mg/m² basis are 1.4, ≥ 0.6, and ≥ 3.6 times the maximum daily human
dosage (246 mg/m²) for mouse, rat and rabbit, respectively.
No drug-related teratogenic effects were observed in
progeny of mice (up to 140 mg/kg or 420 mg/m²), rats (up to 80 mg/kg or 480
mg/m²) or rabbits (up to 300 mg/kg or 3600 mg/m²) treated with tramadol by
various routes. Embryo and fetal toxicity consisted primarily of decreased
fetal weights, skeletal ossification and increased supernumerary ribs at
maternally toxic dose levels. Transient delays in developmental or behavioral
parameters were also seen in pups from rat dams allowed to deliver. Embryo and
fetal lethality were reported only in one rabbit study at 300 mg/kg (3600 mg/m²),
a dose that would cause extreme maternal toxicity in the rabbit. The dosages
listed for mouse, rat and rabbit are 1.7, 1.9 and 14.6 times the maximum daily
human dosage (246 mg/m²), respectively.
Non-teratogenic Effects
Tramadol was evaluated in peri- and post-natal studies in
rats. Progeny of dams receiving oral (gavage) dose levels of 50 mg/kg (300 mg/m²
or 1.2 times the maximum daily human tramadol dosage) or greater had decreased
weights, and pup survival was decreased early in lactation at 80 mg/kg (480
mg/m² or 1.9 and higher the maximum daily human dose).
There are no adequate and well-controlled studies in
pregnant women. Tramadol should be used during pregnancy only if the potential
benefit justifies the potential risk to the fetus. Neonatal seizures, neonatal
withdrawal syndrome, fetal death and still birth have been reported during
post-marketing.
Labor And Delivery
RYBIX ODT should not be used in pregnant women prior to
or during labor unless the potential benefits outweigh the risks. Safe use in
pregnancy has not been established. Chronic use during pregnancy may lead to
physical dependence and post-partum withdrawal symptoms in the newborn (see Drug
Abuse And Dependence). Tramadol has been shown to cross the placenta. The
mean ratio of serum tramadol in the umbilical veins compared to maternal veins
was 0.83 for 40 women given tramadol during labor.
The effect of tramadol if any, on the later growth,
development, and functional maturation of the child is unknown.
Nursing Mothers
RYBIX ODT is not recommended for obstetrical preoperative
medication or for post-delivery analgesia in nursing mothers because its safety
in infants and newborns has not been studied. Following a single IV 100 mg dose
of tramadol, the cumulative excretion in breast milk within 16 hours postdose
was 100 μg of tramadol (0.1% of the maternal dose) and 27 μg of M1.
Pediatric Use
The safety and efficacy of RYBIX ODT in patients under 16
years of age have not been established. The use of RYBIX ODT in the pediatric
population is not recommended.
Geriatric Use
In general, dose selection for an elderly patient should
be cautious, usually starting at the low end of the dosing range, reflecting
the greater frequency of decreased hepatic, renal or cardiac function and of
concomitant disease or other drug therapy. In patients over 75 years of age,
daily doses in excess of 300 mg are not recommended (see CLINICAL
PHARMACOLOGY and DOSAGE AND ADMINISTRATION).
A total of 455 elderly (65 years of age or older)
subjects were exposed to tramadol in controlled clinical trials. Of those, 145
subjects were 75 years of age and older.
In studies including geriatric patients, treatment-limiting
adverse events were higher in subjects over 75 years of age compared to those
under 65 years of age. Specifically, 30% of those over 75 years of age had
gastrointestinal treatment-limiting adverse events compared to 17% of those
under 65 years of age. Constipation resulted in discontinuation of treatment in
10% of those over 75.
Drug Abuse And Dependence
Abuse
Tramadol has mu-opioid
agonist activity. RYBIX ODT can be abused and may be subject to criminal
diversion.
Addiction is a primary,
chronic, neurobiologic disease, with genetic, psychosocial, and environmental
factors influencing its development and manifestations. Drug addiction is
characterized by behaviors that include one or more of the following: impaired
control over drug use, compulsive use, use for non-medical purposes, and
continued use despite harm or risk of harm, and craving. Drug addiction is a
treatable disease, utilizing a multidisciplinary approach, but relapse is
common.
“Drug-seeking” behavior is very
common in addicts and drug abusers. Drug-seeking tactics include emergency
calls or visits near the end of office hours, refusal to undergo appropriate
examination, testing or referral, repeated “loss” of prescriptions, tampering
with prescriptions and reluctance to provide prior medical records or contact
information for other treating physician(s). “Doctor shopping” to obtain
additional prescriptions is common among drug abusers and people suffering from
untreated addiction.
Abuse and addiction are
separate and distinct from physical dependence and tolerance. Physicians should
be aware that addiction may not be accompanied by concurrent tolerance and
symptoms of physical dependence in all addicts. In addition, abuse of RYBIX ODT
can occur in the absence of true addiction and is characterized by misuse for
non-medical purposes, often in combination with other psychoactive substances.
Concerns about abuse and
addiction should not prevent the proper management of pain. However all
patients treated with opioids require careful monitoring for signs of abuse and
addiction, because use of opioid analgesic products carries the risk of
addiction even under appropriate medical use.
Proper assessment of the
patient and periodic re-evaluation of therapy are appropriate measures that
help to limit the potential abuse of this product.
RYBIX ODT is intended for oral
use only.
Dependence
Tolerance is the need for
increasing doses of drugs to maintain a defined effect such as analgesia (in
the absence of disease progression or other external factors). Physical
dependence is manifested by withdrawal symptoms after abrupt discontinuation of
a drug or upon administration of an antagonist (see also WARNINGS, Withdrawal).
The opioid abstinence or withdrawal syndrome is
characterized by some or all of the following: restlessness, lacrimation,
rhinorrhea, yawning, perspiration, chills, myalgia, and mydriasis. Other
symptoms also may develop, including irritability, anxiety, backache, joint
pain, weakness, abdominal cramps, insomnia, nausea, anorexia, vomiting,
diarrhea, or increased blood pressure, respiratory rate, or heart rate.
Generally, tolerance and/or withdrawal are more likely to
occur the longer a patient is on continuous therapy with RYBIX ODT.