What are the Common Signs of an Overdose?

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  • Written By: M.C. Huguelet
  • Edited By: Heather Bailey
  • Last Modified Date: 21 September 2018
  • Copyright Protected:
    Conjecture Corporation
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While many people associate the term overdose with the use of illicit drugs, it can in fact refer to the excessive intake of any substance, whether accidental or intentional. In addition to illicit drugs, these substances can include caffeine, alcohol, nicotine, prescription and non-prescription medications, and even vitamins. While the exact signs of an overdose can vary depending on the substance in question, overdose commonly affects the vital signs, the appearance, the awareness, the gastrointestinal system, the muscles, and the liver. Those showing serious signs of an overdose should be taken to an emergency medical facility for evaluation.

Among the most common signs of an overdose are changes to the vital signs. When taken in excess, many substances can cause the heart rate, blood pressure, breathing rate, and temperature to fall. Conversely, some substances may cause these factors to spike. Extreme changes in the vital signs can indicate that the substance which has been taken in excess is causing one or more of the body’s organs to shut down.

Changes to one’s physical appearance are also among the most common signs of an overdose. The skin of the overdosed individual may appear to be drained of color, or may be extremely flushed and sweaty-looking. In addition, the individual’s pupils may appear to be enlarged or extremely small, and his eyes may seem to be sunken.


Alterations to awareness also commonly accompany an overdose. The overdosed individual may seem to be excessively irritable, paranoid, panicked, confused, sleepy, or euphoric. He may have difficulty concentrating or remembering. In extreme cases, he may lose consciousness or even fall into a coma.

An upset gastrointestinal system is also among the most common signs of an overdose. The overdosed individual may experience moderate to severe stomach pains. He may also vomit, have diarrhea, or both.

Often, the muscles are affected by an overdose. They may cramp, becoming extremely stiff and painful. Conversely, they may spasm uncontrollably.

Normally, the liver plays a key role in filtering the blood to remove toxins. During an overdose, however, levels of a foreign substance in the blood may be too high for the liver to process. Such excessively high substance levels can cause the liver to fail, an overdose symptom which can prove life-threatening if it is not quickly treated.

In addition to understanding that overdose can be caused by an extremely wide variety of substances, it is also important to know that just small amounts of a particular substance can cause an overdose in an individual with a sensitivity to that substance. Therefore, signs of an overdose should be taken seriously, even if the overdose has been caused by a “normal” dosage of a substance which is usually harmless. Those showing signs of an overdose should be taken to an emergency medical facility for evaluation.



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Post 3

Wow, I didn't know that muscles can be affected from an overdose. I always thought that overdose causes mental issues like confusion or stomach issues like nausea. Side effects like headaches and cramps are probably common too, but I had never heard of muscle spasm as an overdose sign.

I suffered from a severe muscle spasm last month. I wonder if I had overdosed on something without realizing.

Post 2

@fify-- Did you take many vitamin C supplements?

It's difficult to overdose on vitamin C. Some people even say that it's impossible because it's a water soluble vitamin. So the excess will be removed from the body, it will not be stored.

But if you take very large amounts of it, you may experience some uncomfortable gastrointestinal signs and symptoms like nausea and vomiting. If you have these symptoms or if you suspect that you overdosed, it's a good idea to go to a hospital. But if you don't have any symptoms, you're probably going to be fine.

Overdosing is a greater risk with fat soluble vitamins because they are stored in the body. And of course, it's a risk with all medications and herbs.

Post 1

What are the symptoms of vitamin C overdose?

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