Are glycolax and miralax the same?

Short answer:
Yes and no.

• Same active ingredient – Both Glycolax and MiraLAX contain polyethylene glycol 3350 (PEG 3350), the same osmotic laxative that draws water into the colon to soften stool and promote bowel movements.
• Different brand names / formulations – Glycolax is the generic/brand name used in some countries (e.g., the UK, Canada, parts of Europe), while MiraLAX is the U.S. brand name sold by Pfizer (and later by other manufacturers). The basic formula is identical, but the tablets or sachets may differ slightly in appearance, excipients, and packaging.
• Dosage and dosing schedules – Because the strength per unit (e.g., 17 g sachet, 20 g sachet, 5 g tablet) can vary between brands, you should follow the specific dosing instructions that come with the product you have.
• Availability – MiraLAX is commonly sold over‑the‑counter in the U.S., whereas Glycolax might be found in pharmacies outside the U.S. or sold under different brand names in those markets.

What PEG 3350 does

• Osmotic action: PEG 3350 is a large, non‑absorbable polymer. It stays in the intestinal lumen and attracts water, which softens stool and stimulates peristalsis.
• Safety profile: It’s generally well tolerated. The most common side effects are mild abdominal cramping or bloating. Rarely, it can cause dehydration if you don’t drink enough fluids.
• Uses: Primarily for short‑term relief of constipation, but also used for bowel preparation before colonoscopy, or in certain conditions like chronic constipation or irritable bowel syndrome (IBS) with constipation.

Practical tips if you’re switching between the two

1. Read the label – Confirm the amount of PEG 3350 per sachet/tablet.
2. Match the dose – If you’re used to taking a 17 g sachet of MiraLAX, find the equivalent strength of Glycolax (often a 17 g or 20 g sachet).
3. Adjust fluids – Always drink plenty of water with PEG 3350 products.
4. Watch for side‑effects – Mild cramping is normal; if it becomes severe or you notice dizziness/rapid heartbeat, stop the product and contact your provider.
5. Pregnancy & lactation – PEG 3350 is considered safe during pregnancy and lactation, but you should still consult your healthcare provider.

Bottom line

Glycolax and MiraLAX are essentially the same medication—both are PEG 3350 laxatives. The difference is largely a matter of brand name and regional availability. If you’re switching from one to the other, just make sure the dose is equivalent and follow the instructions that come with the product. If you have any medical conditions or are taking other medications, it’s always a good idea to double‑check with your pharmacist or doctor before changing brands.