Acupuncture has been around for centuries and has been practiced all over the world. It is relatively safe. Just like any other invasive procedure, there will always be some risks. It should be done in a sanitary environment and by a licensed practitioner.

Side-effects may come in the form of hematoma or slight bruising in the places surrounding the points where the needles were inserted. The bruises will eventually fade in a few days.

There might be some minor bleeding when the needles are taken out, but this can be stopped immediately by applying pressure with the use of cotton or gauze on the area.
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The sight of the needles may cause some people to feel faint and become dizzy. This may be due to the conscious or unconscious fear of needles and can be dealt with by having the person to be treated lie down.

In rare instances, complications such as nerve injury might happen due to the nerves being unintentionally punctured. Deep needling usually has the higher number of possible complications because it might hit an organ like the kidney or the lung.

Unsanitary practice of acupuncture may result in the contraction of infectious diseases like hepatitis B or C and HIV. Though it helps ease morning sickness, there is a very slim possibility that it can terminate pregnancy because a point may be stimulated causing the production of oxytocin and ACTH.