Narcan Warnings and Precautions
Before using Narcan, precautions and warnings should be reviewed with your healthcare provider to help minimize risks for withdrawal symptoms, allergic reactions, and other potentially serious complications. Check with your healthcare provider before using this drug if you have certain health conditions, such as problems with your heart, kidneys, or liver. Safety concerns also apply to women who are pregnant or breastfeeding.
- Been taking opioid medicines, either for a medical or nonmedical reason
- Been using illegal or street drugs
- Liver disease, such as cirrhosis, liver failure, or hepatitis
- Kidney disease, such as kidney failure (renal failure)
- Heart disease
- Any allergies, including to foods, dyes, or preservatives.
In addition, let your healthcare provider know if you are:
- Pregnant or thinking of becoming pregnant.
You should also tell your healthcare provider about all other medications you are taking, including prescription and nonprescription medicines, vitamins, and herbal supplements.
Some warnings and precautions to be aware of prior to using Narcan include the following:
- Narcan can cause withdrawal symptoms in people who have been taking opioid medications regularly, including illegal drugs like heroin that bind to opioid receptors. This also includes newborns of mothers who took opioids during pregnancy. Symptoms of withdrawal may include:
- Body aches
- Fast heart rate (tachycardia)
- Runny nose
- Nausea and vomiting
- Nervousness, restlessness, or irritability
- Shivering or trembling
- Abdominal (stomach) cramps
- High blood pressure (hypertension)
- Seizures, excessive crying, and extremely active reflexes in newborns.
- Because the effects of many opioids last longer than those of Narcan, repeated doses may be needed. Your healthcare provider will observe you closely when you receive this medicine and give you multiple doses of Narcan if necessary.
- Narcan is only effective for treating respiratory depression caused by opioid medications. It will not reverse respiratory depression due to other causes. In addition, the drug may not be completely effective, or higher doses may be needed, when used to treat respiratory depression from opioids that are partial agonists or mixed agonists/antagonists, such as buprenorphine (Buprenex®, Butrans®, Subutex®, Suboxone®) and pentazocine (Talacen®, Talwin®, Talwin® Nx).
- Because opioid overdoses can be serious, other medical interventions may be needed in addition to Narcan, such as medical assistance with breathing (artificial ventilation) and medications to raise blood pressure (known medically as vasopressors).
- When used in high doses after an operation, Narcan may cause agitation and reverse pain relief. It can also cause potentially life-threatening symptoms when used postoperatively, especially in people who have heart disease. Such symptoms may include:
- This medicine should be used cautiously in people with liver disease or kidney disease.
- Narcan may react with a few other medications (see Narcan Drug Interactions).
- It is unknown if Narcan passes through breast milk. Therefore, if you are breastfeeding or plan to start, you should discuss this with your healthcare provider prior to using the drug (see Narcan and Breastfeeding).
- Narcan is a pregnancy Category B medication, which means it is generally considered safe for use during pregnancy (see Narcan and Pregnancy).