A recent TikTok from the University of Bristol’s student TV station sparked conversation for giving students advice on how to take MDMA.

The UBTV video, overlaid with text reading ‘how often should I take breaks from MDMA’, was presented by a spokesperson from The Drop, part of Bristol Drugs Project, which offers information and support for people using drugs recreationally.

So far, it’s racked up more than 35,000 views, but comments aren’t all positive, with the top liked reply simply saying ‘or don’t do it’.

However, given new research shows a third (32%) of British 23-year-olds have tried hard drugs such as cocaine, ketamine and ecstasy — triple the figure for 17-year-olds — judgement-free information like this is vital from a perspective of harm reduction.

Instead of abstinence, the harm reduction approach to drugs accepts that people will take them, regardless of any ban or warning put in place.

It therefore focuses on practical strategies to minimise negative impacts, from overdose prevention to signposting to addiction support services, with the ultimate goal being to prevent drug-related deaths (now at the highest numbers since records began in England in Wales).

Encouraging safer use is a key cornerstone of this approach, and leaving gaps between ‘sessions’ can go a long way in keeping drug users safe.

Recreational vs dependent

Organisations like The Drop acknowledge that many people won’t stop using drugs, and won’t get addicted.

The harm reduction approach offers advice for people that occasionally use drugs recreationally, for pleasure and enjoyment.

Addiction however, is a chronic condition, defined by the NHS as ‘not having control over doing, taking or using something to the point where it could be harmful to you’.

A person who is dependent or addicted to drugs has a compulsion to use, despite the negative impact the habit may be having on their life.

Dr Rayyan Zafar, neuropsychopharmacologist at Drug Science, tells Metro: ‘A break [between drug taking] isn’t just letting the drug leave the system, it’s about giving the brain and body the time to reverse potential neuro-adaptations that happen in response to the drug.’

These include changes to your tolerance level, a temporary decrease of different chemicals or hormones, and overstimulation of parts of the brain required for you to function at your best.

‘On top of that is the restoration of sleep and appetite, and the reduction of harm to organs,’ he adds.

According to Dr Zafar, ‘it’s a frequency in the dose that drives the harm, not single one-off exposures per se,’ which is why breaks are so important. The risks also multiply if you combine different substances.

The fact is, there are no ‘safe use guarantees’ when it comes to either dose or time limit, and beyond the potential health dangers, getting caught in possession of illegal drugs can also carry a penalty of up to seven years in prison.

However, if you are going to take them, these science-backed guidelines may help lessen the long-term impact.

GHB, heroin, methamphetamine and crack cocaine

Although all drugs can be harmful, GHB, heroin, methamphetamine and crack cocaine have been omitted from this piece, as Dr Zafar says they have no safe limits between use — and because they’re so extremely dangerous, should be avoided altogether.

MDMA: 3 months

Although Dr Zafar says six to eight weeks is the minimum amount of time you should leave between MDMA doses, he recommends a ‘more conservative’ break of three months (as advised in the UBTV TikTok).

There’s no evidence to suggest recreational MDMA use causes any long-term damage to the adult brain, but because it stimulates the production ofserotonin — a hormone related to stress, sleep and temperature — Dr Zafar says it’s possible that, over time, the changes to your brain’s serotonin system may affect how you feel and think.

Recent studies suggest the brain doesn’t fully-form until age 32, so extra caution is also advised for younger people.

Despite this though, Dr Zafar adds that MDMA is ‘by and large, in the way that people use it, a very safe drug.’

MDMA-related fatalities are typically the result of inadequate temperature regulation, taking it alongside other drugs, and high-potency pills, with the risks increasing for first-time users and women (because of how it interacts with the oestrogen and vasopressin in their bodies).

Need support?

If you’re concerned about your own or a loved one’s drug use, the NHS recommends speaking to your GP or visiting the Frank website to find specific support services near you.

If you’re having trouble finding the right sort of help, call the Frank drugs helpline on 0300 123 6600 and they can talk you through your options.

Cocaine: At least a month

Cocaine may be one of the most popular recreational drugs in the UK, but according to Dr Zafar, there’s ‘no evidence-based safe gap’ between sessions.

At the very least, he recommends avoiding consecutive days, as there’s a ’24-fold heart attack increase in the hour after using cocaine’ which decreases over time, but a break of a month or more is preferred.

‘Even weekly use of cocaine can lead to something called dopamine sensitisation,’ Dr Zafar continues. ‘So weekend binge culture can actually make your brain become more dependent on it, and cause sleep loss, anxiety, dependence, risk and cardiotoxicity (heart damage) when combined with alcohol.’

Cannabis: 1 month

‘Tolerance to cannabis is linked to the CB1 receptor,’ explains Dr Zafar. That’s the part of the brain that helps regulate things like appetite, pain, memory and mood. ‘There’s evidence that its density normalises four weeks after abstinence in daily users,’ says Dr Zafar.

After two weeks without a joint, your tolerance is reduced, but a month’s break is better for a ‘complete reset’ of the CB1 receptor, where you can ‘noticeably’ feel a difference.

In terms of regular users, he says dependency often develops as people try to avoid the withdrawal that comes with CB1 receptor downregulation.

‘Basically, the cannabis will dampen it down, which is a response to kind of having loads of like THC in the system,’ he adds. ‘It tries to reduce the number of receptors to reduce the effects… But then, when you stop using the drug, you have the withdrawal like effect, and then they’ll grow back up.’

Amphetamines: 1 month

If you’ve taken amphetamines such as speed, you need to wait a month before doing so again, both to combat the effects of sleep deprivation and overheating, and to avoid falling into chronic use, which ‘is linked to neurochemical and neuroanatomical changes.’

Dr Zafar explains: ‘There are brain changes and also psychiatric risk, with reviews of alterations to the dopamine systems in the brains of people who regularly use amphetamines.’

You may have heard that one of these drugs, mephedrone – also known as M-CAT or meow meow – is being trialled as a psychiatric drug, and has been advocated as a reduced-harm alternative to cocaine by Drug Science founder, Professor David Nutt, a former UK government drug advisor, because it’s less neurotoxic and causes fewer deaths.

‘But the issue with M-CAT is people generally tend to stay up for days on it, where it’s harder to stay up to days on cocaine because of the pharmacokinetic profile,’ adds Dr Zafar. ‘So we can’t take away from the harms entirely.’

Hallucinogens: 3 to 7 days

‘Psychedelics like LSD and psilocybin (magic mushrooms) tolerance builds up really fast, but it also drops really fast, so you probably need around three to seven days to clear acute tolerance,’ says Dr Zafar.

Essentially, if you take hallucinogens more than once or twice within a week, you’ll feel less each time — which is why in clinical psychedelic therapy programs researchers schedule breaks of two to four-weeks between doses.

On retreats, however, people are often given two or three doses over the course of as many days, and when it comes to ‘meaning making’, ‘the longer the breaks are, the more insight.’

Keep in mind too, that while there’s limited evidence of neurotoxicity with these drugs, in some cases they can precipitate psychosis, and it’s important to take them in a comfortable and supportive environment because they’re ‘quite powerful’.

Ketamine: Minimum 2 weeks

Alongside avoiding frequent use, Dr Zafar says you should ‘think weeks between sessions – at minimum two weeks – and stop immediately if you get urinary symptoms’.

He continues: ‘There is a cumulative bladder and urinary tract toxicity that occurs, which is a standout harm for ketamine, and the risk rises significantly with regular patterns… For example, using ketamine at least three times a week over a period of two years has been shown to result in alterations in bladder function.’

This level of use applies to a ‘small and increasing number of people’, but even though it’s not likely to have bladder issues with infrequent recreational comsumption, you should still be careful and seek medical advice if you do experience any worrying symptoms.

After all, it’s better to be safe than sorry.

Alcohol: 2 weeks

You may not consider alcohol as a ‘drug’, but despite the fact it’s readily available and widely used, Professor David Nutt, considers it one of the most harmful.

And although the NHS guideline is no more than 14 units a week, Dr Zafar says ‘no amount of alcohol is safe for the body’ due to how it ‘affects every organ in the body destructively.’

The impact also worsens following ‘cumulative exposure’, with studies showing that three days of drinking in a row causes your liver to start producing ‘alcohol-related fatty deposits’, which can then lead to cirrhosis.

To mitigate this somewhat, Dr Zafar recommends spreading your drinking you out as much possible, from taking specific days off booze each week to practicing Dry January and Sober October for a bigger reset.

He says most people begin to feel more energetic, less irritable and have better sleep better after two weeks abstinence.

‘If you go and have a binge again, then you then got to wait another two weeks to get back to the point that you’ve just earned,’ Dr Zafar concludes.

Tips for harm reduction

Whatever the substance, Dr Zafar recommends these tips to limit its negative impact on your health:

• Don’t mix drugs.
• Avoid binges.
• Watch out for warning signs, from psychological symptoms like anxiety and low mood to physical ones like chest pains, breathlessness and headaches; ‘that’s your body’s way of basically saying you need to be in recovery.’
• Check the drug’s potency. Legally-available testing kits can give you an example of what’s inside a drug, as well as the potential potency of the drug, helping you make an informed decision on how much you should take.
• Seek support as soon as you feel use is becoming problematic, for example if ‘you’re beginning to feel like when you’re off the drug, you’re not feeling great’ — ‘that might be the start of a bigger problem.’

This article was first published on January 22, 2026.

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A doctor at B.C. Children’s Hospital says he was delighted to tell one of his patients that he had been cured of his condition.

Nineteen-year-old Kelowna, B.C., resident Ty Sperle was diagnosed at the age of five with chronic granulomatous disease.

“The helpful way to think about it is that we’re surrounded by bacteria and funguses and other things that can infect us,” Dr. Stuart Turvey, a pediatric immunologist at B.C. Children’s Hospital and a professor of pediatrics at UBC, told Global News.

“We have an immune system that I like to think of as a suit of armour that protects us and because of Ty’s issue, he really had a big hole in that suit of armour. And so different bacterial or fungal infections could sneak in really at any time and cause serious or even life-threatening infections. So it’s a tough disease to live with. People with this disease don’t live long healthy lives.

Turvey said that over the years, Sperle has had to take pills, antibiotics and antifungals in an attempt to boost his immune system, but he has still battled some very serious infections that are hard to treat and get under control.

“It’s a disease that I think you’re always looking over your shoulder, wondering, is today the day that that infection is going to sneak in?” he said.

Turvey said there have been other treatments in the past for chronic granulomatous disease, involving hematopoietic stem cell transplantation, or a bone marrow transplant, but only if there is an optimal healthy donor and Sperle didn’t have one.

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When Turvey heard about a clinical trial by U.S.-based Prime Medicine being offered at a limited number of sites, he jumped at the chance to register Sperle.

The only site in Canada offering the trial was Montreal’s Sainte-Justine University Hospital.

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“I think one of the defining things about what we do at B.C. Children’s Hospital, and particularly in immunology, is have these very large global networks,” Turvey said.

“And so we are very connected globally. And I knew that there had been plans in the works for many years to start what we call a gene therapy trial for Ty’s condition. And so I think kept abreast of that and then I think it also shows that tackling these problems can’t be just one hospital or one province or even one country.”

Turvey described the process of curing Sperle involved changing his DNA.

“He was born with that, you could think of that like a spelling mistake that meant that his immune system wasn’t constructed properly and this prime editing technique is a little bit like a word processor, where they can go in and correct that spelling mistake in Ty’s very own cells and then return those cells to Ty’s body,” he said.

“And so he now has corrected cells that are his cells. So they’re not going to attack his body or they’re not going be rejected by his body. So this is really the ultimate treatment for this type of condition.”

Turvey said this is what pediatricians dream about — identifying life-threatening conditions and being able to cure them.

“The success of Ty’s treatment, this curative miracle, really builds on decades, even centuries of science research,” he said.

“We understood DNA, then we were able to sequence the human genome about 20 years ago. And now we’re in the era of being able to rewrite and edit that genome. And this technology that Ty benefited from was something that we call CRISPR-Cas9, or a version of that CRISPR technology that won the Nobel Prize quite recently.”

Turvey added that he is delighted that Sperle can now just go and live his life.

“For me, it means that I don’t have to worry with Ty about all those problems that could come down the line,” he said.

“So I can see Ty as a friend and watch him grow up as a healthy man and I don’t have to worry about all those potential difficulties. So yeah, I’m happy not to have to be Ty’s doctor anymore because he doesn’t have chronic granulomatous disease.

“I’d like to be his friend.”

&copy 2026 Global News, a division of Corus Entertainment Inc.

It was a pestilence of biblical proportions.

Officials in Spain’s Canary Islands are sounding alarm bells after an epic swarm of locusts descended upon the popular vacation destination, as seen in dramatic footage circulating on social media.

Over the past few days, the scenic islands of Lanzarote, Tenerife, Gran Canaria and Fuerteventura have been beset by the biblical plague of short-horned grasshoppers, the Express reported. Originally hailing from the Sahara Desert in Africa, the notorious crop pests were reportedly driven to the sunny Spanish isles by humid yet mild temperatures.

Lanzarote was particularly hard hit with the insects swarming the tourist hotspots of Arrecife, Costa Teguise, Famara, Uga and Tahíche.

Footage shows the bugs darkening the skies like something out of one of the “Mummy” movies.

While the locusts don’t pose a threat to people, they could potentially devastate the island’s agricultural industry, including vineyards, if the swarm snowballs into a full-blown infestation as it did years ago in the islands.

Borne aloft by Easterly winds and accompanied by airborne Sahara Desert dust, desert locusts are the “world’s most destructive migratory pest,” according to the Food and Agriculture Organization of the United Nations.

A 250-acre swarm of the critters — which can contain 80 million individuals — is capable of consuming what 35,000 humans eat in a day, meaning their feast could quickly become people’s famine.

In accordance, the government of Lanzarote has put its environmental sector on high alert for the next 48 hours.

However, they remain confident that the swam will not escalate into a full-on plague, the Daily Mail reported.

“The next two days are going to be key,” declared Francisco Fabelo, who oversees the Environment of the Cabildo. “If they are adult specimens that have arrived exhausted, they will die and nothing will happen.”

He added, “If we see copulations, that would mean that they are reproducing. We would have to see it between this afternoon and tomorrow.”

Meanwhile, Theo Hernando, secretary general of the Association of Farmers and Ranchers of the Canary Islands (Asaga) said wind-borne locust plagues from Africa are “common” and nothing to worry about in “isolated cases.”

‘They arrive very weakened, they are not in a position to settle or reproduce,” he assured. “Nature itself takes its course and many times they end up being preyed upon by birds.”

That being said, the Canary Islands are no strangers to devastating locust plagues. In a serious incident in October 1958, desert locusts from Africa pillaged the Canary Islands, especially the South of Tenerife, wreaking havoc on tomato and potato plantations.

In response, the Ministry of Agriculture dispatched planes to fumigate from the air, while residents and farmers tried to combat the grasshoppers from the ground using bonfires, noise and poisoned baits.

This reportedly followed a similar scourge that ravaged 10,000 hectares of crops in the region just four years earlier.

Researchers at McGill University say they’ve made progress in improving a technology that can convert human urine into electricity.

The study examined how microbial fuel cells (MFC) perform when supplied with different concentrations of urine.

According to Vijaya Raghavan, professor at McGill and co-author of the study, these systems use bacteria to break down organic waste while producing small amounts of power.

While microbial fuel cells are already known for their ability to treat wastewater and generate electricity, researchers say there has been limited study into how urine concentration affects their performance.

“While MFCs are known to clean wastewater and generate electricity, the specific effects of different urine concentrations on their function and pollutant removal efficiency are still not well understood,” said Raghavan.

“This study addresses that gap by systematically examining how varying urine proportions affect the system.”

For the experiment, researchers built four microbial fuel cells and supplied them with mixtures of synthetic wastewater and human urine at concentrations of 20, 50 and 75 per cent.

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Over a two-week period, the team monitored electricity production, pollutant removal and overall treatment efficiency.

They found that higher urine concentrations, particularly between 50 and 75 per cent, improved power generation and supported stronger microbial activity.

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“Urine contains essential ions and organic compounds that support rapid microbial growth, which improves power generation and pollutant breakdown,” Raghavan said.

Raghavan said the findings could have practical implications in regions where traditional wastewater treatment or energy infrastructure is limited.

He said the technology could eventually be used in rural sanitation systems, disaster relief operations and off-grid communities.

Because microbial fuel cells produce measurable electrical signals in response to pollution levels, researchers say the systems may also function as low-cost wastewater monitoring tools.

Beyond energy production, researchers say the approach aligns with broader sustainability efforts by turning waste into a usable resource.

“Using urine as a resource supports sustainable sanitation and nutrient recovery, reducing pressure on freshwater systems,” Raghavan said.

He added that scientific advances continue to demonstrate how collaboration and innovation can address global challenges.

“It is very encouraging. Being exposed to global systems as a professor working within Canada, I see the importance that science and technology bring,” Raghavan said.

“Today the ozone hole is closing, which is a very positive example of how global efforts can come together to solve humanitarian problems. I have many more hopes for how we can use science and technology for sustainability.”

&copy 2026 Global News, a division of Corus Entertainment Inc.