Blacking out test

Welcome.

The two main reasons for blacking out are insufficient blood flow to the brain and abnormal electrical activity within the brain (a seizure).

While both of these sound scary, in reality most episodes of blacking out are not related to life threatening health problems.

This guide is designed to provide insight into why you passed out. It is not a diagnostic tool or a substitute for evaluation by a health professional.

The questions are ones your doctor is likely to ask you. Your answers provide a path to better understanding of the common reasons for losing consciousness.

Let's begin.

Certain situations demand emergency medical care.

Do any of the following apply to you?

- Chest pain or shortness of breath before or after you passed out

- Bloody or black stools

- Severe headache

- Recent blow to the head

- A heart condition

Yes, one of those applies to me.

No, none of those apply to me.

That's good. But even without these symptoms, you might need rapid medical evaluation.

You always need to contact your doctor immediately if:

- This has never happened to you before

- Your reason for blacking out in the past was never diagnosed

- This most recent episode is not exactly the same as the past episodes for which you did have a diagnosis

- You are surprised that it has happened again at this time

Do any of the above apply to you?

Yes, one or more do apply to me.

No, none of those apply to me.

Great. Now let's explore some of the common reasons for blacking out.

Did you feel lightheaded just before you blacked out?

Yes, I did feel lightheaded.

No, I don't recall feeling lightheaded.

Call your doctor or medical advice center now.

If you are not advised to get immediate medical care, please continue.

Click here to continue with the guide.

Let's explore some of the common reasons for blacking out.

Did you feel lightheaded just before you blacked out?

Yes, I did feel lightheaded.

No, I don't recall feeling lightheaded.

Although you don't recall feeling lightheaded immediately before passing out, you might have noticed getting lightheaded at other times, especially when standing quickly.

Do either or both of the following apply to you?

- I stood up quickly from a lying or sitting position before I blacked out.

- Although I did not get lightheaded this time, I have felt lightheaded with standing in the past.

Yes, one or both applies to me.

No, neither applies to me.

So far, your answers indicate that you have never felt lightheaded with standing and you did not stand up quickly this time before you blacked out.

Which of the following applies to you?

I woke up in bed.

I slumped over in a chair.

I ended up on the floor.

I have no idea what happened next.

It may be that you had a drop in your blood pressure. If blood pressure falls too much too quickly, it can cause you to black out. Usually you would feel lightheaded before you actually lost consciousness.

Let's assume that you don't remember feeling lightheaded this time.

Did you fall and injure yourself when you blacked out?

Yes, I did injure myself.

I have no injury related to blacking out.

Did the lightheaded feeling start after you stood up from a lying or sitting position?

Yes, that's when I felt lightheaded.

No, not that I recall.

So far, your answers indicate that you felt lightheaded, but don't remember standing up quickly before you blacked out.

Which of the following applies to you?

I woke up in bed.

I slumped over in a chair.

I ended up on the floor.

I have no idea what happened next.

If the blackout results in an injury from falling to the floor, there are two concerns.

- The cause of the blackout

- Even if it was a simple faint, you could break a bone or hit your head the next time you black out.

Did you suffer any injury from the blackout?

Yes, I injured myself.

Nope, no injury.

If the blackout results in an injury from falling to the floor, there are two concerns.

- The cause of the blackout

- Even if it was a simple faint, you could break a bone or hit your head the next time you black out.

Did you suffer any injury from the blackout?

Yes, I injured myself.

Nope, no injury.

That's good. But there could still be a serious reason for loss of consciousness.

Call for immediate medical help. Call 911 if necessary. Do not attempt to drive.

You will need prompt evaluation. There are multiple possibilities:

- Low blood sugar

- Dehydration

- Heart related problem

- A seizure

- Alcohol or drug effect

Call for immediate medical help. Call 911 if necessary. Do not attempt to drive.

You will need prompt evaluation. There are multiple possibilities:

- Low blood sugar

- Dehydration

- Heart related problem

- A seizure

- Alcohol or drug effect

It may be that you had a drop in your blood pressure. If blood pressure falls too much too quickly, it can cause you to black out.

Call your doctor for advice.

Your doctor will consider whether this could be:

- Low blood sugar

- Dehydration

- Heart related problem

- A seizure

- Alcohol or drug effect

Continue with this guide after making the call.

Click here to continue with the guide.

In this situation, it is often difficult to know if you actually blacked out or just fell asleep.

If you are unsure, call your doctor for advice.

If you still feel lightheaded when you wake up, your blood pressure may be too low for you.

Click here to continue with the guide.

Quite a few medications can make your blood pressure drop. Even if a medication is not the primary cause, it may be a significant contributor.

Types of medications that most often cause postural hypotension (a drop in blood pressure due to a change in body position) and lightheadedness with standing include:

- Blood pressure medicines

- Beta blockers

- Calcium channel blockers

- Diuretics (water pills)

- Nitroglycerin and other nitrates

- Tricyclic antidepressants

Do you take any of the above medications?

Yes, I take one or more of these medications.

No, I don't take any of these.

Did you fall and injure yourself when you blacked out?

Yes, I did injure myself.

I have no injury related to blacking out.

That's good.

Lightheadedness is often caused by more than one factor. And if blood pressure drops quickly, you can pass out.

Many medications cause lightheadedness with standing. Even if a medication is not the primary cause, it may be a significant contributor.

Types of medications that most often cause postural hypotension (a drop in blood pressure due to a change in body position) and lightheadedness with standing include:

- Blood pressure medicines

- Beta blockers

- Calcium channel blockers

- Diuretics (water pills)

- Nitroglycerin and other nitrates

- Tricyclic antidepressants

Do you take any of the above medications?

Yes, I take one or more of these medications.

No, I don't take any of these.

Always worrisome. Even if this was a simple faint, you should notify your doctor. The next black out could cause even worse injury.

Lightheadedness is often caused by more than one factor. And if blood pressure drops quickly, you can pass out.

Many medications cause lightheadedness with standing. Even if a medication is not the primary cause, it may be a significant contributor.

Types of medications that most often cause postural hypotension (a drop in blood pressure due to a change in body position) and lightheadedness with standing include:

- Blood pressure medicines

- Beta blockers

- Calcium channel blockers

- Diuretics (water pills)

- Nitroglycerin and other nitrates

- Tricyclic antidepressants

Do you take any of the above medications?

Yes, I take one or more of these medications.

No, I don't take any of these.

Many other medications can potentially cause the problem.

Have you started any other new medication, herb, or supplement?

Yes.

No.

If you have had a recent illness, such as a bad cold or the flu, you could have easily gotten behind in your fluid intake. This is especially true if you had nausea, vomiting, or diarrhea. The lightheadedness may occur even a couple days after the other symptoms have resolved.

Have you had a recent illness that might be a factor?

Yes, I have had a recent illness.

No, I have not had a recent illness.

Ask your pharmacist if what you are taking might be contributing to the lightheadedness, or call your doctor's office for advice.

There may be other reasons for your lightheadedness.

Click here to continue with the guide.

Your problem might be resolved by adjusting your medications. This is especially true if you recently started one of these or you increased the dose.

Call your doctor's office for advice.

There may be other reasons for your lightheadedness. Continue with this guide after calling your doctor.

Click here to continue with the guide.

If you have had a recent illness, such as a bad cold or the flu, you could have easily gotten behind in your fluid intake. This is especially true if you had nausea, vomiting, or diarrhea. The lightheadedness may occur even a couple days after the other symptoms have resolved.

Have you had a recent illness that might be a factor?

Yes, I have had a recent illness.

No, I have not had a recent illness.

So far, your answers indicate that neither something you take nor any recent illness is contributing to your lightheadedness with standing.

It may be that you just don't drink enough fluid even though you may not be thirsty. If your urine has a darker yellow color than usual, this would support mild dehydration.

Increase your fluid intake. If you don't have high blood pressure, fluid retention, or heart failure, consider adding a little salt to your diet.

Please continue with the guide.

Click here to continue.

Increase your fluid intake. If you don't have high blood pressure, fluid retention, or heart failure, consider adding a little salt to your diet.

Please continue with the guide.

Click here to continue.

Some people are prone to getting lightheaded, especially people who have fainted in the past. Doctors call simple fainting spells vasodepressor syncope.

Normally when blood pressure starts to fall our heart rate speeds up to compensate. During a simple faint, blood pressure falls and heart rate does the opposite of what it should -- it slows down. If you are standing, not enough blood gets pumped to the brain.

Have you had fainting or near fainting spells in the past?

Yes I have.

No, this hasn't happened to me.

At this time it would be very helpful to have measurements of your blood pressure and pulse (heart rate). The best time to check blood pressure and pulse would be during an episode of lightheadedness. But it may be helpful even if you feel fine now.

Which statement about measuring blood pressure and heart rate applies to you?

I can measure both.

I can only measure my blood pressure.

I can only take my pulse.

I cannot do either one.

At this time it would be very helpful to have measurements of your blood pressure and pulse (heart rate). The best time to check blood pressure and pulse would be during an episode of lightheadedness. But it may be helpful even if you feel fine now.

Which statement about measuring blood pressure and heart rate applies to you?

I can measure both.

I can only measure my blood pressure.

I can only take my pulse.

I cannot do either one.

That's okay.

If you are still lightheaded after drinking more fluids and eating a little extra salt, then call your doctor's office to arrange an appointment.

Check your heart rate by taking your pulse lying down. Stand up and measure it again while you continue to stand. Wait three minutes, unless you are too lightheaded to continue standing, and measure your pulse again.

Which of the following best describes what happened to your pulse when you stood up?

Same or faster pulse

Slower pulse

Assuming that you are not taking any medications that slow down your heart rate, this indicates an abnormal response to standing. If your blood pressure falls, normally your heart tries to pump out more blood by beating faster.

There may be a problem with your autonomic nervous system. This can occur in people with diabetes, some genetic disorders, and some rare diseases.

Call your doctor's office for advice and to arrange an appointment.

If you get lightheaded now as you stand, it is likely that you need more fluid, and possibly a little extra salt. Since you don't know your blood pressure, we need to make an assumption that your blood pressure did fall a little. Increase your fluid intake. If your symptoms persist, call your doctor for advice.

Check your blood pressure lying down. Stand up and measure it again while you continue to stand. Wait three minutes, unless you are too lightheaded to continue standing, and measure your blood pressure one more time.

Which of the following best describes what happened to your blood pressure when you stood up?

Same or higher blood pressure

Lower blood pressure

This usually means that you need more fluid, and possibly a little extra salt. If your symptoms don't rapidly improve, call your doctor for advice.

Since your blood pressure is not falling, right now you should be getting enough blood to your brain. If you are currently lightheaded or dizzy, there is likely some other reason. Increase your fluid intake. If your symptoms persist despite robust fluid intake, call your doctor's office for advice.

Check your blood pressure and heart rate lying down. Stand up and measure both while you continue to stand. Wait three minutes, unless you are too lightheaded to continue standing, and measure your blood pressure and pulse again.

Which of the following best describes what happened to your blood pressure and/or pulse when you stood up?

Same or higher blood pressure

Lower blood pressure, faster pulse

Lower blood pressure, same or slower pulse

Assuming that you are not taking any medications that slow down your heart rate, this indicates an abnormal response to standing. If your blood pressure falls, normally your heart tries to pump out more blood by beating faster.

There may be a problem with your autonomic nervous system. This can occur in people with diabetes, some genetic disorders, and some rare diseases.

Call your doctor's office for advice and to arrange an appointment.

This usually means that you need more fluid, and possibly a little extra salt. If your symptoms don't rapidly improve, call your doctor for advice.

Since your blood pressure is not falling, right now you should be getting enough blood to your brain. If you are currently lightheaded or dizzy, there is likely some other reason. Increase your fluid intake. If your symptoms persist despite robust fluid intake, call your doctor's office for advice.

Call 911. You could be having a heart attack, a dangerous heart rhythm problem, internal bleeding, or bleeding inside your head.

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