Update on Maximum Recommended
Dosages for Local Anesthesia
CLINICIANS SHOULD BE AWARE
OF CURRENT FOOD AND DRUG
APPROPRIATE DOSE FOR
INDIVIDUAL PATIENTS. By Arthur C. DiMarco, DMD,
and Kathy Bassett, RDH, MEd
The United States Food and Drug Administration
(FDA) Center for Drug Evaluation
and Research, Office of Pharmaceutical
Science, Informatics and Computational
Safety Analysis created and consistently
updates maximum recommended dosages (MRDs) for
local anesthetic drugs, although some clinicians may not
know they exist.1 Many oral health professionals use the
MRDs published in the most popular textbooks on local
anesthesia when calculating drug dosages for patients,
which may differ significantly from the values used in the
FDA-approved recommendations (Table 1).
Table 1. Click to view
Oral health professionals—particularly
those in the Western US—have
been guided for a number of years by
lower MRD values than those
approved by the FDA.2–4 There are
benefits to following lower MRDs,
such as enhancing patient safety. As
long as the values administered are
within the FDA recommendations,
there is no breach of these guidelines.
However, maintaining two different
sets of guidelines can be confusing for
the dental team, as Stanley F.
Malamed, DDS, a leading expert in
local anesthesia, noted in the July
issue of Dimensions of Dental Hygiene.5
Removing the possibility of this confusion
provides a strong rationale for
eliminating the nonFDA established
values.5 At this time, not everyone has
adopted the higher values; for example,
the American Academy of Pediatric
Dentistry (AAPD) continues to list
the lower values in its monograph
(Table 2).5,6 Like the AAPD, other
organizations, individual clinicians,
and clinics that use the lower MRDs
provide an additional layer of safety
to their protocols without compromising
treatment or comfort.
Table 2. Click to view
The impact of the differences in the
recommendations can be illustrated
using the following example with
2% lidocaine, 1:100,000 epinephrine.
The lower values for lidocaine are
2 mg/lb maximum, with an absolute
maximum of 300 mg per appointment.
3 When calculating the MRD
using these lower values, a healthy
150-lb individual may receive eight cartridges
of 2% lidocaine, 1:100,000 epinephrine,
rounded down to the nearest
half cartridge.3,4 The established FDA
recommendations are 3.2 mg/lb with
an absolute maximum of 500 mg per
appointment.2 When using these values, the result is significantly different:
a maximum of 13 cartridges may be administered, rounded
down to the nearest half cartridge.2 Note that the actual maximum
number of cartridges that may be safely administered to patients in this
example is not 13; the MRD is limited by the epinephrine content to
11 cartridges.4 When using the lower values, the drug that limits
the maximum number of cartridges is the local anesthetic drug
(first example of eight cartridges; 8<11). When using the FDA values,
the limiting drug is epinephrine (second example of 11 cartridges;
The use of articaine requires an important modification. The mg/lb
MRD for articaine is the same in both sets of recommendations.
Through at least 2010, product inserts for 4% articaine, 1:100,000 epinephrine
list an absolute MRD of seven cartridges, which is approximately
500 mg.7 The current FDA recommendation lists a 3.2 mg/lb
maximum, with no absolute maximum; however, there is a maximum
limit of 4% articaine, 1:100,000 epinephrine, based on the epinephrine
content of 11 cartridges.7 In addition to articaine insert changes, the
current recommendation for 0.5% bupivacaine, 1:200,000 epinephrine,
is an absolute maximum of 90 mg. MRD information for bupivacaine
delineated by pound is no longer available in the US. In Canada, the
recommendations for bupivacaine are 0.9 mg/lb and 2.0 mg/kg.2
Although the FDA has provided MRDs for local anesthetic
drugs (Table 1), patient response to drug dosage cannot
always be predicted. Two equal doses of the same anesthetic
agent can produce markedly different responses in two different
patients. Hyper-responders, for example, may respond to less than
maximum doses with signs and symptoms of overdose. These
individuals join a number of other patients who do not fit easily
into dose recommendations, including those for whom typical
doses result in finite, but relatively prolonged, periods of soft tissue
In addition to observing MRDs, the administration of local anesthetic
drugs continues to be guided by several important factors, including
the area to be anesthetized, vascularity of the tissues, technique, and
individual tolerances. Perhaps the most important advice to follow
comes from a similarly-worded statement that may be found in all local
anesthetic product inserts:"The lowest dosage needed to provide effective
anesthesia should be administered."8
- National Library of Medicine. Daily Med. Available at:
Accessed September 17, 2013.
- Malamed S. Handbook of Local Anesthesia. 6th ed. St. Louis:
Elsevier Mosby; 2013.
- Malamed S. Handbook of Local Anesthesia. 5th ed. St. Louis:
Elsevier Mosby; 2004.
- Bassett K, DiMarco A, Naughton D. Local Anesthesia for Dental
Professionals. Upper Saddle River, NJ: Pearson; 2009.
- Malamed SF. What’s new in local anesthesia. Dimensions of Dental
- American Academy of Pediatric Dentistry. Guideline on Use of Local
Anesthesia for Pediatric Dental Patients. Available at: www.aapd.org/
media/Policies_Guidelines/G_LocalAnesthesia.pdf. Accessed September
- Drug Information Online. Articaine and Epinephrine Injection.
Available at: www.drugs.com/pro/articaine-and-epinephrineinjection.
html. Accessed September 18, 2013.
- National Library of Medicine. Daily Med: 4% articaine, 1:100,000
epinephrine product insert. Available at: dailymed.nlm.nih.gov/ daily
med/archives/fdaDrugInfo.cfm?archiveid=28573. Accessed September
From Dimensions of Dental Hygiene. October 2013;11(10):28–29,31.