Common Numbness of tongue, Decreased urination, Allergic reaction, Itching, Application site irritation, Chest tightness, Diarrhoea, Fever, Dizziness, Shortness of breath, Muscle weakness, Stomach upset.

Expert advice for Harmless Syrup

Consult your doctor if you have any of the following medical conditions: kidney disease, myasthenia gravis (neuromuscular disease characterized by very weak muscles and unusual tiredness), porphyria (a rare blood pigment disorder that affects skin and other organs) or asthma (difficulty in breathing).
Caution should be taken in premature and new-born babies as the kidneys are not fully developed or in children younger than 10 years of age who have diarrhea or an infection of the stomach or bowel.
Do not drive or operate heavy machinery because you may feel sleepy or dizzy while being treated with colistimethate.
Do not consume alcohol while taking colistimethate as it may worsen the side effects.
Tell your doctor if you are or planning to become pregnant or are breastfeeding.