Constipation Relief and Laxatives: A Plain-English Guide (Australia)

Constipation is one of the most common reasons Australians stand in the pharmacy aisle feeling a bit unsure. The shelves are full of laxatives that all promise relief, but they work in very different ways and at very different speeds. The good news is that you usually do not need to reach for a product first at all. Most constipation responds to a few simple changes — more fibre, more fluids and more movement. When those are not enough, the trick is choosing the right type of laxative for your situation rather than just grabbing the first box you see. This guide walks you through both.

What Counts as Constipation?

There is no single 'normal' when it comes to how often you should open your bowels — anywhere from three times a day to three times a week can be perfectly healthy. Constipation is less about a magic number and more about a change from your usual pattern. Common signs include going less often than normal, stools that are hard, dry or lumpy, having to strain, a feeling that you have not fully emptied, or needing to pass fewer than three bowel motions a week. Bloating, mild cramping and a loss of appetite can come along for the ride too.

Constipation is often triggered by everyday things: not enough fibre or fluid, a sudden drop in activity, travel, ignoring the urge to go, pregnancy, ageing, or certain medicines (including some strong pain relievers, iron supplements and antacids). Most of the time it is short-lived and settles with a few adjustments.

Start Here: Lifestyle Steps Before Laxatives

Before you spend money on a laxative, it is worth giving the basics a real go. These steps may help ease constipation and, just as importantly, may help keep you regular over the long term — something no laxative is designed to do on its own.

• radio_button_uncheckedBuild up your fibre gradually: fibre adds bulk and softness to stools, making them easier to pass. Aim for around 25-30g a day from wholegrains, fruit, vegetables, legumes, nuts and seeds. The key word is gradually — adding a lot of fibre overnight can cause bloating and wind, so build it up over a week or two and let your gut adjust.
• radio_button_uncheckedDrink enough fluid: fibre works best when there is enough water in the system, so the two go hand in hand. Most adults do well aiming for roughly 6-8 glasses of fluid a day, and more in hot Australian weather or if you are very active. This matters even more if you are taking a bulk-forming or osmotic laxative, which both rely on water to do their job.
• radio_button_uncheckedKeep moving: regular physical activity helps keep the bowel moving. You do not need a gym membership — a daily walk, some light exercise, or simply breaking up long periods of sitting can make a genuine difference. This is one reason constipation is so common during travel or illness, when we tend to move far less than usual.
• radio_button_uncheckedDo not ignore the urge — and check your posture: when you feel the urge to go, try not to hold on, as repeatedly ignoring it can make constipation worse over time. Many people also find toilet posture helps: sitting with your knees a little higher than your hips (resting your feet on a small footstool), leaning forward slightly with your elbows on your knees, and relaxing rather than straining. This position helps straighten the lower bowel and can make passing a motion easier.

OTC Laxative Types Decoded

If lifestyle steps are not enough, there are five main types of over-the-counter laxative available in Australian pharmacies. They differ in how they work, how fast they act, and who they suit best. Understanding the differences is the single most useful thing you can do before buying — it is the difference between relief and a frustrating (or uncomfortable) trial-and-error process.

• radio_button_uncheckedBulk-forming (fibre) laxatives — psyllium, Metamucil, Fybogel: essentially concentrated fibre. Psyllium husk absorbs water in the gut, making stools larger, softer and easier to pass. One of the gentler options, well suited to mild or ongoing constipation. Take with a full glass of water and keep fluids up through the day.
• radio_button_uncheckedOsmotic laxatives — macrogol (Movicol), lactulose (Actilax): draw water into the bowel, which softens the stool and helps it move along. Macrogol is widely used and generally well tolerated, making it a popular choice for moderate constipation; lactulose is a sugar-based osmotic laxative that works similarly. Drinking enough fluid is important, as the water has to come from somewhere.
• radio_button_uncheckedStool softeners — docusate (Coloxyl): work by letting water and fats penetrate the stool, making it softer and easier to pass without straining. Often suggested where straining is best avoided — for example after surgery, after childbirth, or for people with haemorrhoids. May be combined with a stimulant in some products (such as Coloxyl with Senna) for an added push.
• radio_button_uncheckedStimulant laxatives — bisacodyl (Dulcolax), senna (Senokot): prompt the muscles of the bowel wall to contract and push the stool along. The fastest of the oral options, generally working within about 6-12 hours, which is why people often take them at night. They can cause cramping and are intended for occasional, short-term use only — needing one for more than about a week is a reason to see your pharmacist or GP.
• radio_button_uncheckedGlycerol (glycerin) suppositories: inserted into the rectum and act locally to lubricate and gently stimulate a bowel motion. Their main advantage is speed, typically working within about 20-45 minutes. Like stimulants, best kept for occasional use rather than relied on day to day.

Laxative Types Compared at a Glance

Here is a side-by-side look at the main laxative types — how each one may help, roughly how fast it works, and who it tends to suit, along with key cautions. Use it as a starting point for a conversation with your pharmacist, not as a substitute for one.

Using Laxatives Safely

Laxatives are generally safe for occasional use when you follow the label, but a few habits keep them helpful rather than harmful.

• radio_button_uncheckedDo not rely on stimulant laxatives long-term. They are for occasional, short-term use. Regular use can lead to the bowel becoming less responsive and to dependence — if you feel you need one most days, see your pharmacist or GP.
• radio_button_uncheckedDrink enough fluid, especially with bulk-forming and osmotic laxatives — both need water to work and can otherwise make constipation worse.
• radio_button_uncheckedGive gentler options time. Bulk-forming, osmotic and softener laxatives are not instant; allow a day or more before deciding they have not worked.
• radio_button_uncheckedAlways read the label and stick to the recommended dose. More is not better, and overuse can upset your fluid and salt balance.
• radio_button_uncheckedCheck before combining laxatives or adding one on top of regular medicines or supplements — your pharmacist can flag interactions.
• radio_button_uncheckedIf constipation keeps coming back, look at the cause (fibre, fluid, activity, medicines) rather than reaching for a laxative every time.

Red Flags: When to See a GP

Constipation is usually harmless and short-lived. But some warning signs mean you should stop self-treating and see a doctor, because they can point to something that needs proper assessment. Book an appointment with your GP — or seek urgent care if symptoms are severe — if you notice any of the following.

Frequently Asked Questions

What gives the quickest relief for constipation?

Among over-the-counter options, glycerol (glycerin) suppositories tend to act fastest, often within about 20-45 minutes. Oral stimulant laxatives such as bisacodyl (Dulcolax) or senna (Senokot) generally work within around 6-12 hours, which is why they are often taken at night. Both are intended for occasional, short-term use only. If you need fast relief regularly, that is a reason to see your pharmacist or GP rather than to keep using stimulants.

What is the best laxative in Australia?

There is no single 'best' laxative — the right one depends on your situation. For mild or ongoing constipation, a bulk-forming laxative such as psyllium (Metamucil) is a gentle starting point. For moderate constipation, an osmotic laxative such as macrogol (Movicol) is generally well tolerated. If straining is the issue, a softener such as docusate (Coloxyl) may suit. Stimulants such as Dulcolax or Senokot act fastest but are for short-term use. Your pharmacist can match a product to your needs.

Is Coloxyl or Movicol better?

Neither is universally 'better' — Coloxyl (docusate) is a gentle stool softener, while Movicol (macrogol) is a stronger osmotic laxative for moderate constipation. See our full Coloxyl vs Movicol comparison guide for the details.

Is there a homemade laxative that works right away?

No home remedy reliably works instantly. That said, some gentle measures may help over hours to days: drinking more water, a warm drink, and increasing fibre through fruit (such as kiwifruit, prunes or pears), vegetables and wholegrains. Prunes and prune juice are a traditional remedy and contain both fibre and natural sorbitol, which can have a mild laxative effect. These are worth trying for mild constipation, but if you need a quick result, an over-the-counter option is more predictable. See a GP if home measures and pharmacy products are not helping.

How can I relieve constipation immediately?

For the fastest over-the-counter relief, a glycerol suppository typically works within about 20-45 minutes, and an oral stimulant such as bisacodyl usually works within roughly 6-12 hours. Alongside this, make sure you are drinking enough fluid, stay gently active, and use a footstool to improve toilet posture. Keep fast-acting laxatives for occasional use — if constipation is frequent or you have any red-flag symptoms such as blood in the stool or severe pain, see your GP.

What empties the bowels quickly?

Fast-acting options that may help empty the bowels include glycerol suppositories (around 20-45 minutes) and oral stimulant laxatives such as bisacodyl or senna (around 6-12 hours). These are designed for occasional use, not for routine bowel emptying. If you find yourself needing to 'clear out' regularly, the better approach is to address the underlying cause — fibre, fluids, activity and any contributing medicines — and to speak with your pharmacist or GP.