This is not dangerous, but it can be disruptive to your loved one’s life. You may want to consult a doctor or find support to help you manage this issue.

Surviving a traumatic brain injury or stroke can change someone in many ways. So can living with a progressive neurological condition like Alzheimer’s disease, multiple sclerosis (MS), or amyotrophic lateral sclerosis (ALS).

When you care for someone who has one of these conditions, you might notice changes in their mental abilities as the condition progresses. You may notice changes in their personality too.

People who have a brain injury or neurological disease can also develop pseudobulbar affect (PBA), which causes sudden, uncontrollable, and exaggerated emotional outbursts. If the person you care for suddenly begins to laugh or cry without reason or cannot stop their emotional outbursts, they likely have PBA.

Here are six signs and symptoms to look for, plus tips on what to do if you think your loved one has PBA.

A person with PBA may respond to funny or sad situations by laughing or crying, just like anyone else. But the responses are more intense, or they last longer than the situation warrants.

A humorous scene in a movie can provoke gales of laughter that continue long after everyone else has stopped laughing. Saying goodbye to a friend after lunch might lead to tears that keep flowing several minutes after the friend has left.

In addition to exaggerated responses, someone with PBA may cry when they’re not sad or laugh when there’s nothing funny going on. Their reaction may have no relationship to the emotion they’re feeling at the time.

With PBA, there may be no connection between the experience at hand and the emotional reaction to it. Someone with the condition may burst into tears at a carnival or laugh out loud at a funeral — two atypical reactions in such situations.

PBA can pop up suddenly and unexpectedly in almost any type of situation. A person might be completely calm one second and then suddenly tear up or burst into laughter for no obvious reason.

Most of us have experienced a fit of the giggles in which we could not stop laughing, no matter how hard we tried. People with PBA feel this way whenever they laugh or cry. No matter what they do, they cannot stop the emotional outpouring.

Emotions can switch from one extreme to the other in people with PBA. Laughter can quickly turn to tears, and vice versa.

The shifts are due to a problem with the part of the brain that normally regulates emotional responses to situations.

After the laughing or crying has subsided, the person’s usual emotions return.

The duration of symptoms can help you distinguish PBA from depression. Crying that’s caused by PBA lasts a few minutes at a time. With depression, symptoms can last for many weeks or months.

PBA is not dangerous, but it can be disruptive to your loved one’s life. Knowing that an emotional outburst is likely can make it uncomfortable for people with this condition to be in social situations.

For this reason, and because PBA can overlap with or mimic depression, it’s important to have your loved one contact a doctor.

The neurologist who treats their neurological condition can diagnose and treat PBA too. You might also take them to a psychiatrist or neuropsychologist for an evaluation.

A few medications are available to treat PBA. They include a drug called dextromethorphan/quinidine (Nuedexta) and antidepressants.

Nuedexta is the only medication that the Food and Drug Administration (FDA) has approved to treat PBA. But antidepressants may be prescribed off-label.

Nuedexta and antidepressants do not cure PBA, but they can reduce the intensity and frequency of emotional outbursts.

Off-label drug use

Off-label drug use means that a drug approved by the FDA for one purpose is used for a different purpose that hasn’t yet been approved.

But a doctor can still use the drug for that purpose. This is because the FDA regulates the testing and approval of drugs — not how doctors use drugs to treat their patients. So your doctor can prescribe a drug however they think is best for your care.