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Miralax vs. Ex-Lax

Polyethylene glycol 3350 (Miralax) and senna (Senokot, Ex-Lax) are both over-the-counter medications used to treat occasional constipation, but they work differently. Miralax is an osmotic laxative that draws water into your colon to soften stool, typically taking 1 to 3 days to produce a bowel movement. In contrast, senna is a stimulant laxative that makes your gut muscles contract to push stool out, usually working within 6 to 12 hours. Miralax is a tasteless powder mixed with a beverage and taken once a day, while senna comes in tablets and liquids that can be taken once or twice a day. Miralax is generally gentler, causing less cramping and bloating, whereas senna can cause stomach cramps and changes in electrolyte levels if misused. Neither medication is recommended for long-term use and should be used for no more than a week without consulting a healthcare provider.