1. Sweaty Palms

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Sweaty palms is one of the biggest signs that you might be afraid of heights! If this happens to you when you're up high, watching a video about heights or even just thinking about heights, you might have acrophobia. This occurs due to our body's fight or flight mode when put in a position that makes us feel in danger!
2. Rapid Heartbeat

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If your heart rate starts increasing rapidly when you are stationary, it can be a sign that you are experiencing high levels of stress. This physiological response is a common symptom that people with acrophobia, or any phobia of that matter, experience when they are high up.
3. How Steep Are Those Stairs?!

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It might seem crazy, but feeling nervous when walking up an especially steep set of stairs could be a sign that you have a more general fear of heights! If you find yourself avoiding stairs that seem to be never ending, or avoiding stairs at all costs then you could have acrophobia.
4. Starting To Get Dizzy Now...

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Dizziness is a horrible feeling, and often happens when you stand up too quickly or if you've banged your head against the door. People who have acrophobia often report feelings of dizziness when they are high up somewhere - if this happens to you as well it could mean that you have acrophobia.
5. Going Out Of Your Way To Avoid Heights

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Do you find yourself avoiding walking up a steep street? Or maybe you avoid walking up a hill when on a hike? If your journey somewhere consists of going the long way around to avoid going anywhere near something high up, this is a telltale sign that you might be afraid of heights.
6. Scared To Look Up At A Tall Building

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If you live in New York you're probably used to super tall buildings, but have you ever stood at the bottom of one and looked straight up? Most people can without a problem, but some people start feeling queasy or lightheaded after a couple of seconds, and some people avoid looking up at tall buildings altogether!
7. Fear Of Being On A Bridge

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Some bridges can be pretty high up which make people with acrophobia avoid them. To make it worse, bridges aren't built to be completely rigid, which means they actually move slightly in high winds or bad weather. This is normal, but if you're afraid of heights and the bridge you're on starts swaying, it won't be a fun time.
8. Wanting To Crawl On All Fours

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Humans have really good balance when stood up, but heights can make the people who are afraid of them feel like they're losing their balance. Crawling on all fours can help people ground themselves when their dizziness makes them think they'll fall over.
9. Afraid To Look Out Of A High Window

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When you're high up in an apartment building it can be super disorientating if you look out the window and try to look at the ground below. Suddenly your depth perception feels all out of whack and you can't seem to pinpoint the distance between you and different locations.
10. You Can't Stand On A Balcony

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Standing on your apartment balcony might give you the same reaction as looking out of a high window, except this time you don't have a massive glass barrier protecting you from falling off the building. Pretty much all balconies have a barrier, but it feels way more dangerous than just looking out the window.
11. Roller Coasters Are A No-Go

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Rollercoasters can be super fun, but they don't always go to plan. There are plenty of incidents where the ride has had to do an emergency stop and has left the previously excited adrenaline seekers stuck at the top of the highest point of the highest ride in the park. Enough to give anyone an unhealthy dose of acrophobia.
12. Avoiding Talking About Heights

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A lot of people visualize situations in their mind when they are thinking through a problem or imagining what they would do in certain situations. Talking about things can create strong images in your mind and, for some people, even just talking about heights is enough to induce a phobia-reaction.
13. Heart Palpitations

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Lots of people have heart palpitations and they're not usually a sign of anything serious, though in some cases it can be a stress response. People with phobias, such as being afraid of heights, often report that their heart feels like it's skipping a beat when they're exposed to their fears.
14. Heights Make Your Mouth Dry

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We've all had a feeling of dry mouth at some point in our live, and it's usually a sign that you've not drank enough water. However, it can also mean that the person experiencing this is nervous or anxious about something. People with acrophobia often report that their mouth feels dry.
15. Losing Balance When Up High

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Slacklining is a sport that involves balancing on a moving rope, and even the best-balanced individuals will find themselves losing their balance and falling to the ground. Not to bad when you're only 1ft in the air, but imagine feeling like you're losing your balance when you're halfway up Mount Rainier.
16. Can't Watch Videos Of Heights

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We've all seen those videos on YouTube of crazy climbers at the top of a really tall building looking over the edge. It makes most people feel on edge that something terrible will happen, but if you're already afraid of heights then you won't even be able to watch the video in the first place.
17. You Start Hyperventilating

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When you hyperventilate, your breathing becomes rapid and uncontrolled, which can lead to feeling really dizzy or light-headed. Hyperventilation is a state of complete panic and is often associated with a panic or anxiety attack, something that is common with acrophobia sufferers.
18. You're Afraid Of Losing Control

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There are lots of things in life that you can't control, but we do have control of our own bodies and actions. However, when people are confronted with something they fear they can often feel like they're not in control of themselves, which can create more panic - especially if they're standing on a high bridge.
19. Queasy does it...

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Feeling like you're going to be sick is one of the worst feelings you can have, especially if it is combined with other symptoms of anxiety. People often start feeling nauseous when they look up at a high building or if they're looking out the window on the top floor.
20. You Start Having Panic Attack

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Panic attacks can happen to anyone at any given moment and sometimes it isn't obvious what the trigger is. Symptoms can include feeling dizzy, feeling out of control or feeling like you might die. A panic attack can sometimes happen when someone doesn't know that they have a fear of heights until they find themselves somewhere that is high.
21. You Get Vertigo

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Vertigo is the sensation that the objects around you are moving or spinning, and it can feel like your head is spinning around. It can cause people to feel off-balance, have their vision affected or even cause people to fall over. Some people have it so severe that they can't even complete daily tasks.
22. They Have An Intense Fear Of Death

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Most people have had a fear of dying at some point in their lives, but people who are afraid of heights have a really intense fear that they will die if they happen to be high up somewhere. Even if there they are perfectly safe, they can't help the feeling like something bad can happen.
23. They Begin Screaming Or Crying

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People with acrophobia can exhibit their stress in different ways. People who are scared of heights can often begin screaming or even crying when they find themselves in a high place, and it is an uncontrollable response that won't stop until they can either calm down or find a way back down to the ground.
24. Feeling Scared When Thinking About Heights

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For a lot of people who are scared of heights, it's mostly triggered when they're high up or if they see a video of people up high. However, in some rare cases, even the thought of heights can be a big problem and can cause symptoms of fear, this is in extreme cases of acrophobia.
25. Tingling Feeling In Hands And Feet

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Not quite the same as pins and needles, as this is more of a numbing sensation. When you feel anxious, the blood vessels in your body can constrict which can lessen the blood flow to your hands and feet. If you experience this when you're up high, it could be a symptom of acrophobia.
26. Wanting to Escape When You're High Up

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Wanting to run away from a fear instead of standing up to it is a really common tactic when dealing with a phobia, as it means the person doesn't have to mentally process why they might have the fear in the first place. This is especially true with people who have a fear of heights.
27. Fear Of Falling When Up High

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Falling over is embarrassing at the best of times, but falling over when you're high up is a lot more dangerous. This doesn't stop most people from going on a hike, but the intense fear of falling off the edge of something is enough to stop acrophobia-sufferers.
28. Your Fear Of Heights Impacts Your Day

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In extreme cases, acrophobia is more than getting sweaty palms when watching a video about heights. It can have a real impact on your day, and people are unable to stop worrying and thinking about heights and it stops them from going about their daily routine.
29. Needing To Hold Onto Something

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Holding onto something can help people keep their balance and help them to not fall over or down when climbing. However, people who are afraid of heights might still feel the need to hold onto to something even if there isn't any immediate danger to them.
30. Stay Away From The Edge

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The Grand Canyon doesn't have any barriers around its edge, which means you can walk right up to the edge and peer over to see how high up you are (or how far down the floor of the Grand Canyon is). Sadly there are often a few casualties a year from people falling over the edge, so you certainly won't find people with acrophobia anywhere near the Grand Canyon.