Fourteen years ago, the older drug cousin of semaglutide (Ozempic and Wegovy) came onto the market. The drug, liraglutide, is sold under the brand names Victoza and Saxenda.

Patents for Victoza and Saxenda have now expried. So other drug companies are working to develop “generic” versions. These are likely be a fraction of current cost, which is around A$400 a month.

So how does liraglutide compare with semaglutide?

How do these drugs work?

Liraglutide was not originally developed as a weight-loss treatment. Like semaglutide (Ozempic), it originally treated type 2 diabetes.

The class of drugs liraglutide and semaglutide belong to are known as GLP-1 mimetics, meaning they mimic the natural hormone GLP-1. This hormone is released from your small intestines in response to food and acts in several ways to improve the way your body handles glucose (sugar).

How do they stop hunger?

Liraglutide acts in several regions of the unconscious part of your brain, specifically the hypothalamus, which controls metabolism, and parts of the brain stem responsible for communicating your body’s nutrient status to the hypothalamus.

Its actions here appear to reduce hunger in two different ways. First, it helps you to feel full earlier, making smaller meals more satisfying. Second, it alters your “motivational salience” towards food, meaning it reduces the amount of food you seek out.

Liraglutide’s original formulation, designed to treat type 2 diabetes, was marketed as Victoza. Its ability to cause weight loss was evident soon after it entered the market.

Shortly after, a stronger formulation, called Saxenda, was released, which was intended for weight loss in people with obesity.

How much weight can you lose with liraglutide?

People respond differently and will lose different amounts of weight. But here, we’ll note the average weight loss users can expect. Some will lose more (sometimes much more), others will lose less, and a small proportion won’t respond.

The first GLP-1 mimicking drug was exenatide (Bayetta). It’s still available for treating type 2 diabetes, but there are currently no generics. Exenatide does provide some weight loss, but this is quite modest, typically around 3-5% of body weight.

For liraglutide, those using the drug to treat obesity will use the stronger one (Saxenda), which typically gives about 10% weight loss.

Semaglutide, with the stronger formulation called Wegovy, typically results in 15% weight loss.

The newest GLP-1 mimicking drug on the market, tirzepatide (Mounjaro for type 2 diabetes and Zepbound for weight loss), results in weight loss of around 25% of body weight.

What happens when you stop taking them?

Despite the effectiveness of these medications in helping with weight loss, they do not appear to change people’s weight set-point.

So in many cases, when people stop taking them, they experience a rebound toward their original weight.

What is the dose and how often do you need to take it?

Liraglutide (Victoza) for type 2 diabetes is exactly the same drug as Saxenda for weight loss, but Saxenda is a higher dose.

Although the target for each formulation is the same (the GLP-1 receptor), for glucose control in type 2 diabetes, liraglutide has to (mainly) reach the pancreas.

But to achieve weight loss, it has to reach parts of the brain. This means crossing the blood-brain barrier – and not all of it makes it, meaning more has to be taken.

All the current formulations of GLP-1 mimicking drug are injectables. This won’t change when liraglutide generics hit the market.

However, they differ in how frequently they need to be injected. Liraglutide is a once-daily injection, whereas semaglutide and tirzepatide are once-weekly. (That makes semaglutide and tirzepatide much more attractive, but we won’t see semaglutide as a generic until 2033.)

What are the side effects?

Because all these medicines have the same target in the body, they mostly have the same side effects.

The most common are a range of gastrointestinal upsets including nausea, vomiting, bloating, constipation and diarrhoea. These occur, in part, because these medications slow the movement of food out of the stomach, but are generally managed by increasing the dose slowly.

Recent clinical data suggests the slowing in emptying of the stomach can be problematic for some people, and may increase the risk of of food entering the lungs during operations, so it is important to let your doctor know if you are taking any of these drugs.

Because these are injectables, they can also lead to injection-site reactions.

During clinical trials, there were some reports of thyroid disease and pancreatitis (inflammation of the pancreas). However, it is not clear that these can be attributed to GLP-1 mimicking drugs.

In animals, GLP-1 mimicking drugs drugs have been found to negatively alter the growth of the embryo. There is currently no controlled clinical trial data on their use during pregnancy, but based on animal data, these medicines should not be used during pregnancy.

Who can use them?

The GLP-1 mimicking drugs for weight loss (Wegovy, Saxenda, Zepbound/Mounjaro) are approved for use by people with obesity and are meant to only be used in conjunction with diet and exercise.

These drugs must be prescribed by a doctor and for obesity are not covered by the Pharmaceutical Benefits Scheme, which is one of the reasons why they are expensive. But in time, generic versions of liraglutide are likely to be more affordable.

Sebastian Furness, ARC Future Fellow, School of Biomedical Sciences, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

This time of year, most fridges are stocked up with food and drinks to share with family and friends. Let’s not make ourselves and our guests sick by getting things wrong when preparing and serving food.

As the weather warms up, so does the environment for micro-organisms in foods, potentially allowing them to multiply faster to hazardous levels. So put the drinks on ice and keep the fridge for the food.

But what are some of those food safety myths we’ve long come to believe that aren’t actually true?

Myth 1: if you’ve defrosted frozen meat or chicken you can’t refreeze it

From a safety point of view, it is fine to refreeze defrosted meat or chicken or any frozen food as long as it was defrosted in a fridge running at 5°C or below. Some quality may be lost by defrosting then refreezing foods as the cells break down a little and the food can become slightly watery.

Another option is to cook the defrosted food and then divide into small portions and refreeze once it has stopped steaming. Steam in a closed container leads to condensation, which can result in pools of water forming. This, combined with the nutrients in the food, creates the perfect environment for microbial growth. So it’s always best to wait about 30 minutes before refrigerating or freezing hot food.

Plan ahead so food can be defrosted in the fridge, especially with large items such as a frozen turkey or roll of meat. If left on the bench, the external surface could be at room temperature and micro-organisms could be growing rapidly while the centre of the piece is still frozen!

Myth 2: Wash meat before you prepare and/or cook it

It is not a good idea to wash meats and poultry when preparing for cooking. Splashing water that might contain potentially hazardous bacteria around the kitchen can create more of a hazard if those bacteria are splashed onto ready-to-eat foods or food preparation surfaces.

It is, however, a good idea to wash fruits and vegetables before preparing and serving, especially if they’re grown near or in the ground as they may carry some dirt and therefore micro-organisms.

This applies particularly to foods that will be prepared and eaten without further cooking. Consuming foods raw that traditionally have been eaten cooked or otherwise processed to kill pathogenic micro-organisms (potentially deadly to humans) might increase the risk of food poisoning.

Fruit, salad, vegetables and other ready-to-eat foods should be prepared separately, away from raw meat, chicken, seafood and other foods that need cooking.

Myth 3: Hot food should be left out to cool completely before putting it in the fridge

It’s not OK to leave perishable food out for an extended time or overnight before putting it in the fridge.

Micro-organisms can grow rapidly in food at temperatures between 5° and 60°C. Temperature control is the simplest and most effective way of controlling the growth of bacteria. Perishable food should spend as little time as possible in the 5-60°C danger zone. If food is left in the danger zone, be aware it is potentially unsafe to eat.

Hot leftovers, and any other leftovers for that matter, should go into the fridge once they have stopped steaming to reduce condensation, within about 30 minutes.

Large portions of hot food will cool faster if broken down into smaller amounts in shallow containers. It is possible that hot food such as stews or soup left in a bulky container, say a two-litre mixing bowl (versus a shallow tray), in the fridge can take nearly 24 hours to cool to the safe zone of less than 5°C.

Myth 4: If it smells OK, then it’s OK to eat

This is definitely not always true. Spoilage bacteria, yeasts and moulds are the usual culprits for making food smell off or go slimy and these may not make you sick, although it is always advisable not to consume spoiled food.

Pathogenic bacteria can grow in food and not cause any obvious changes to the food, so the best option is to inhibit pathogen growth by refrigerating foods.

Myth 5: Oil preserves food so it can be left at room temperature

Adding oil to foods will not necessarily kill bugs lurking in your food. The opposite is true for many products in oil if anaerobic micro-organisms, such as Clostridium botulinum (botulism), are present in the food. A lack of oxygen provides perfect conditions for their growth.

Outbreaks of botulism arising from consumption of vegetables in oil – including garlic, olives, mushrooms, beans and hot peppers – have mostly been attributed to the products not being properly prepared.

Vegetables in oil can be made safely. In 1991, Australian regulations stipulated that this class of product (vegetables in oil) can be safely made if the pH (a measure of acid) is less than 4.6. Foods with a pH below 4.6 do not in general support the growth of food-poisoning bacteria including botulism.

So keep food out of the danger zone to reduce your guests’ risk of getting food poisoning this summer. Check out other food safety tips and resources from CSIRO and the Food Safety Information Council, including testing your food safety knowledge.

Cathy Moir, Team leader, Microbial and chemical sciences, Food microbiologist and food safety specialist, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.