Laxative Comparison Tool
| Product | Type | Onset (hours) | Duration (hours) | Cost (NZD/month) | Best For |
|---|---|---|---|---|---|
| Duphalac (Lactulose) | Osmotic | 24–48 | 24–72 | $20–$30 | Long-term, Liver Health |
| Milk of Magnesia (Mg(OH)₂) | Mineral Osmotic | 6–12 | 12–24 | $10–$15 | Quick Relief, Budget |
| Polyethylene glycol 3350 (MiraLAX) | Polymer Osmotic | 12–24 | 24–48 | $12–$18 | Long-term, General |
| Psyllium Husk | Fiber Bulk-forming | 12–18 | 24–48 | $8–$12 | Budget, Fiber Intake |
| Senna | Herbal Stimulant | 6–12 | 12–24 | $5–$10 | Quick Relief, Short-term |
| Bisacodyl | Stimulant | 6–12 | 12–24 | $7–$12 | Short-term Relief |
| Glycerin Suppository | Rectal Lubricant | 0.5–2 | 2–4 | $4–$8 | Emergency Relief |
Adjust filters to see personalized recommendations.
- For long-term use, osmotic laxatives like Duphalac are gentler than stimulants.
- Quick relief often comes from stimulants or rectal suppositories.
- Psyllium husk offers the lowest cost for ongoing treatment.
If you’re battling constipation, you’ve probably heard the name Duphalac comparison tossed around. But does it really beat the other options on the market? This guide breaks down Duphalac (lactulose) side‑by‑side with the most common alternatives, so you can decide which one fits your lifestyle, budget, and health needs.
What is Duphalac?
Duphalac is a brand‑name formulation of lactulose, a synthetic sugar that works as an osmotic laxative. It was first introduced in the 1960s and is prescribed for chronic constipation and hepatic encephalopathy. When you take Duphalac, lactulose isn’t absorbed in the small intestine; it reaches the colon unchanged, where gut bacteria break it down into acids that draw water into the bowel, softening stool and stimulating peristalsis.
How Lactulose Differs from Other Laxatives
Unlike stimulant laxatives that trigger bowel muscles directly, lactulose’s osmotic action is gentler and often preferred for long‑term use. It also has the added benefit of reducing ammonia levels in patients with liver disease. However, its sweet taste and the need for consistent dosing can be drawbacks for some users.
Popular Alternatives to Duphalac
- Magnesium hydroxide (commonly sold as Milk of Magnesia) - a mineral‑based osmotic laxative that neutralizes stomach acid while pulling water into the colon.
- Polyethylene glycol 3350 (known as MiraLAX) - a high‑molecular‑weight polymer that retains water in the stool without being absorbed.
- Psyllium husk - a soluble fiber supplement that expands when mixed with liquid, adding bulk and moisture to stool.
- Senna - an herbal stimulant that activates the colon’s muscle fibers, prompting quicker evacuation.
- Bisacodyl - a synthetic stimulant available in tablets or suppositories, often used for short‑term relief.
- Glycerin suppository - a rectal lubricant that softens stool locally, ideal for occasional constipation.
Side‑by‑Side Comparison
| Product | Type | Typical Dose | Onset (hours) | Duration (hours) | Common Side Effects | Estimated Cost (NZD/month) |
|---|---|---|---|---|---|---|
| Duphalac (Lactulose) | Osmotic | 15-30ml liquid or 5g powder daily | 24‑48 | 24‑72 | Bloating, gas, mild cramping | ≈$20‑$30 |
| Milk of Magnesia (Mg(OH)₂) | Mineral osmotic | 30‑60ml liquid every 4‑6h | 6‑12 | 12‑24 | Diarrhea, electrolyte imbalance | ≈$10‑$15 |
| Polyethylene glycol 3350 (MiraLAX) | Polymer osmotic | 17g (1 packet) dissolved daily | 12‑24 | 24‑48 | Flatulence, abdominal discomfort | ≈$12‑$18 |
| Psyllium husk | Fiber bulk‑forming | 5‑10g with 8oz liquid daily | 12‑18 | 24‑48 | Bloating, occasional blockage if not enough water | ≈$8‑$12 |
| Senna | Herbal stimulant | 0.5‑1mg tablet daily | 6‑12 | 12‑24 | Cramping, urgency | ≈$5‑$10 |
| Bisacodyl | Stimulant | 5‑10mg tablet at bedtime | 6‑12 | 12‑24 | Stomach pain, electrolyte loss | ≈$7‑$12 |
| Glycerin suppository | Rectal lubricant | 1suppository as needed | 0.5‑2 | 2‑4 | Local irritation, mild bleeding | ≈$4‑$8 |
Choosing the Right Option for You
Consider these three decision points when picking a laxative:
- Duration of use - If you need a chronic solution, an osmotic agent like Duphalac or PEG is usually gentler on the colon. Stimulants such as Senna or Bisacodyl are better suited for short‑term rescue.
- Speed of relief - For rapid action (under 4hours), glycerin suppositories or high‑dose magnesium hydroxide win. Duphalac’s slower onset makes it less ideal for emergencies.
- Health considerations - Patients with kidney disease should avoid magnesium‑based products, while those with liver impairment may benefit from lactulose’s ammonia‑lowering effect.
In practice, many clinicians start patients on a low‑dose osmotic (Duphalac or PEG) and add a fiber supplement like psyllium for added bulk. If the stool remains hard, a short course of a stimulant can break the stalemate.
Practical Tips for Safe Laxative Use
- Always drink plenty of water; osmotic agents pull fluid into the gut, and insufficient hydration can worsen constipation.
- Follow the exact dosing schedule - taking more than recommended rarely speeds up results and raises the risk of diarrhea.
- Monitor electrolytes if you use magnesium hydroxide or bisacodyl for longer than two weeks.
- Notify your GP if you experience severe abdominal pain, blood in stool, or no improvement after a week of therapy.
Frequently Asked Questions
Can I use Duphalac and a fiber supplement together?
Yes. Combining lactulose with a soluble fiber like psyllium can enhance stool softness while providing the bulk that some people miss from a pure osmotic laxative.
Is Duphalac safe for children?
Pediatric dosing is lower - typically 5ml of the liquid formulation twice daily for children aged 2‑12. Always check with a pediatrician before starting.
What if Duphalac makes me gassy?
Gas is a common early side effect. Starting with a half‑dose and slowly titrating up can ease the problem. Drinking warm water after each dose often helps.
Are there any drug interactions with lactulose?
Lactulose has few interactions, but it can affect the absorption of some oral antibiotics. Separate the doses by at least two hours to avoid reduced efficacy.
Which laxative is the cheapest for long‑term use?
Bulk‑forming fibers like psyllium often have the lowest monthly cost, followed closely by generic magnesium hydroxide. Duphalac is moderately priced, while branded PEG products sit in the mid‑range.
Bottom line: Duphalac shines when you need a gentle, long‑lasting solution, especially if liver health is a concern. For quick relief or lower cost, magnesium hydroxide, PEG, or fiber may be better fits. Use the comparison table and decision guide above to match the right laxative to your unique situation.
Manisha Deb Roy
October 9, 2025 AT 15:45Duphalac’s osmotic action makes it a solid long‑term pick; it's gentle on the colon and even helps lower ammonia for liver patients.
Just remember to keep hydratd so the water it pulls into the gut can do its job.