Spread of toxin effects. In some cases, the effect of botulinum toxin may affect areas of the body away from the injection site and cause symptoms of a serious condition called botulism. The symptoms of botulism include: loss of strength and muscle weakness all over the body, double vision, blurred vision and drooping eyelids, hoarseness or change or loss of voice, trouble saying words clearly, loss of bladder control, trouble breathing, trouble swallowing., XEOMIN may cause loss of strength or general muscle weakness, blurred vision, or drooping eyelids within hours to weeks of taking XEOMIN. If this happens, do not drive a car, operate machinery, or do other dangerous activities. What are the possible Side Effects of XEOMIN? XEOMIN can cause serious side effects including:, Xeomin is a botulinum toxin type A, so it works very similarly to Botox (onabotulinumtoxinA), Dysport (abobotulinumtoxinA), Jeuveau (prabotulinumtoxinA-xvfs), and Daxxify (daxibotulinumtoxinA-lanm): by blocking signals between nerves and muscles so the injected muscle can’t contract and wrinkle the skin..