What are the most common side effects of Nayzilam?

The most common side effects of Nayzilam are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

Sleepiness

Headache

Runny nose 

Nasal discomfort 

Throat irritation

There may be other side effects of Nayzilam that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at  or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at  or by calling 866-234-2345.

While less common, the most serious side effects of Nayzilam are described below, along with what to do if they happen.

Severe Allergic Reactions. Nayzilam may cause allergic reactions, which can be serious. Stop using Nayzilam and get help right away if you have any of the following symptoms of a serious allergic reaction.

Risk of Misuse and Addiction. Misusing Nayzilam can lead to serious side effects like coma or death. Misuse means taking a medicine in a way other than how it was prescribed. Use Nayzilam exactly as prescribed. Tell your healthcare provider if you feel that Nayzilam is not working. Call your healthcare provider right away or go to the nearest emergency room if you experience any of the following serious symptoms.

Dependence and Withdrawal Reactions. Nayzilam can cause physical dependence, which means your body relies on the medicine to function properly. If you stop Nayzilam suddenly, it could lead to withdrawal symptoms, which may be life-threatening. Do not stop taking Nayzilam without talking with your healthcare provider. Your healthcare provider will tell you how to stop Nayzilam to reduce the risk of withdrawal reactions. Call your healthcare provider right away or go to the nearest emergency room if you experience any of the following serious symptoms.

Some people may experience the following symptoms of a withdrawal reaction that can last for several weeks to more than 12 months.

Anxiety

Trouble remembering, learning, or concentrating

Depression

Problems sleeping

Feeling like insects are crawling under the skin

Weakness

Shaking

Muscle twitching

Burning or prickling feeling in the hands, arms, legs, or feet

Ringing in the ears

Breathing Problems. Nayzilam may cause slow or shallow breathing, especially if you have breathing problems from another condition or take other medicines that can slow your breathing. Tell your healthcare provider if you develop severe sleepiness or trouble breathing, especially when you start Nayzilam or when your dose is increased.  Get emergency help if you have any of the following symptoms.

Changes in the color of your skin, including bluish color to your lips and fingernails

Confusion

Shortness of breath

Feeling dizzy, lightheaded, or fainting

Changes in your heart rate or rhythm, such as a fast, slow, pounding or skipping heartbeat

Slow or shallow breathing

Excessive sleepiness or trouble staying awake

Risk With Opioid Medicines. Taking Nayzilam with an opioid medicine, such as codeine, morphine, and oxycodone, may lead to severe drowsiness, breathing problems, coma, and death. Get emergency help right away if you experience the following symptoms.

Slow or shallow breathing

Breathing stops (which may lead to the heart stopping)

Excessive sleepiness or trouble staying awake 

Suicidal Thoughts and Actions. Nayzilam may cause suicidal thoughts or actions in a small number of people. If you are about to harm yourself, call 911 or call or text 988, the Suicide & Crisis Lifeline. Call your healthcare provider right away if you have any of the following symptoms.

New or increased thoughts of suicide or death

Suicide attempt

New or increased feelings of anxiety, depression, or other unusual changes in mood or behavior

Decreased Alertness or Coordination. Nayzilam can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how Nayzilam affects you.