Before Using
Allergies
Tell your doctor if you have ever had any unusual or allergic reaction to medicines in this group or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Pediatric
Children may be especially sensitive to the effects of parenteral-local anesthetics. This may increase the chance of side effects.
Geriatric
Elderly people are especially sensitive to the effects of parenteral-local anesthetics. This may increase the chance of side effects.
Pregnancy
Local anesthetics have not been reported to cause birth defects in humans.
Use of a local anesthetic during labor and delivery may rarely cause unwanted effects. These medicines may increase the length of labor by making it more difficult for the mother to bear down (push). They may also cause unwanted effects in the fetus or newborn baby, especially if certain medical problems are present at the time of delivery. Before receiving a local anesthetic for labor and delivery, you should discuss with your doctor the good that this medicine will do as well as the risks of receiving it.
Breastfeeding
It is not known whether local anesthetics pass into breast milk. However, these medicines have not been reported to cause problems in nursing babies.
Drug Interactions
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Other Interactions
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other Medical Problems
The presence of other medical problems may affect the use of medicines in this class. Make sure you tell your doctor if you have any other medical problems, especially:
- Asthma—Increased chance of allergic-like reactions with use of some local anesthetics
- Brain infection or tumor or
- Blood clotting disorders—Increased chance of bleeding with injection of local anesthetics
- Type 2 diabetes mellitus—Use of local anesthetics can cause stress on your heart if you have diabetes mellitus.
- Heart disease—Use of local anesthetics can worsen some kinds of heart disease.
- History of migraine headaches—Use of local anesthetics can worsen headaches.
- Hypertension (high blood pressure) or
- Hypotension (low blood pressure)—Use of local anesthetics can cause hypotension or hypertension.
- Hyperthyroidism—Use of some local anesthetics can cause stress on your heart if you have hyperthyroidism.
- Kidney disease or
- Liver disease—Increased chance of side effects
- Methemoglobinemia—Prilocaine may make this condition worse.
- Peripheral vascular disease—Use of some local anesthetics can make this condition worse or can cause your blood pressure to increase.
- Skin infection or inflammation—Your physician may not want to inject the local anesthetic into infected or inflamed skin because the local anesthetic may not work as well.


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