Heartgard Tablets for Dogs >51 lbs Brown 6
Caution: Federal (U.S.A.) law restricts
this drug to use by or on the order of a licensed veterinarian.
INDICATION: For use in dogs to prevent
canine heartworm disease. HEARTGARD prevents
heartworm disease by eliminating the tissue stage of heartworm larvae (Dirofilaria
immitis) for a month (30 days) after infection.
DOSAGE: HEARTGARD Tablets should be
administered orally at monthly intervals at the recommended minimum dose
level of 6 mcg of ivermectin per kilogram (2.72 mcg/lb) of body weight. (See
ADMINISTRATION). The recommended dosage schedule for prevention of canine
heartworm disease is as follows:
Tablets Per Month
Ivermectin Per Tablet
Color on Carton
Up to 25 lb
26 to 50 lb
51 to 100 lb
Give dogs over 100 lb the appropriate combination of
HEARTGARD is recommended for use in dogs 6 weeks of age and
ADMINISTRATION: The HEARTGARD tablet
should be given so that dogs swallow the whole tablet. (The tablet may be
wrapped in food to encourage consumption.) Care should be taken to see that
the dog consumes the complete dose, and treated animals should be observed
for a few minutes after administration to ensure that part of the dose is
not lost or rejected. If it is suspected that any of the dose has been lost,
redosing is recommended. HEARTGARD Tablets should be given at monthly
intervals during the period of the year when mosquitoes (vectors),
potentially carrying infective heartworm larvae, are active. The initial
dose must be given within a month (30 days) after the first exposure to
mosquitoes. The final dose must be given within a month (30 days) after the
last exposure to mosquitoes.
When replacing another heartworm preventive in a heartworm
disease preventive program, the first dose of HEARTGARD must be given within
a month (30 days) after the last dose of the former medication.
If the interval between doses exceeds a month (30 days), the
efficacy of ivermectin can be reduced. For optimal performance, the tablet
must be given once a month on or about the same day of the month. If
treatment is delayed, whether by a few days or many, immediate treatment
with HEARTGARD and resumption of the recommended dosing regimen minimizes
the opportunity for the development of adult heartworms.
EFFICACY: HEARTGARD Tablets, given
orally using the recommended dose and regimen, are effective against the
tissue larval stage of Dirofilaria immitis for a
month (30 days) after infection and, as a result, prevent the development of
the adult stage.
PRECAUTIONS: All dogs should be tested
for existing heartworm infection before starting treatment with HEARTGARD
(ivermectin) Tablets, which is not effective against adult
D. immitis. Infected dogs must be treated to remove
adult heartworms and microfilariae prior to initiating a program with
While some microfilariae may be killed by the ivermectin in
HEARTGARD at the recommended dose level, HEARTGARD is not effective for
microfilariae clearance. A mild hypersensitivity-type reaction, presumably
due to dead or dying microfilariae and particularly involving a transient
diarrhea, has been observed in clinical trials with ivermectin after the
treatment of some dogs that have circulating microfilariae.
Keep this and all drugs out of the reach of
children. In case of ingestion by humans, clients should be advised to
contact a physician immediately. Physicians may contact a Poison Control
Center for advice concerning cases of ingestion by humans.
ADVERSE REACTIONS: The following adverse
reactions have been reported following the use of HEARTGARD:
Depression/lethargy, vomiting, anorexia, diarrhea, mydriasis, ataxia,
staggering, convulsions and hypersalivation.
SAFETY: HEARTGARD has shown a wide
margin of safety at the recommended dose level in dogs (See PRECAUTIONS for
exceptions) including pregnant or breeding bitches, stud dogs, and puppies
aged 6 or more weeks. In clinical trials, many commonly used flea collars,
dips, shampoos, anthelmintics, antibiotics, vaccines, and steroid
preparations have been administered with HEARTGARD in a heartworm disease
Studies with ivermectin indicate that certain dogs of the
Collie breed are more sensitive to the effects of ivermectin administered at
elevated dose levels (more than 16 times the target use level) than dogs of
other breeds. At elevated doses, sensitive dogs showed adverse reactions
which included mydriasis, depression, ataxia, tremors, drooling, paresis,
recumbency, excitability, stupor, coma and death. HEARTGARD demonstrated no
signs of toxicity at 10 times the recommended dose (60 mcg/kg) in sensitive
Collies. Results of these trials support the safety of HEARTGARD products in
dogs, including Collies, when used as recommended.