The next 20 years hold great opportunities for drugs research. We could see the development of pharmacological substitutes, agents to block the effects of drugs and help people break addictions, and drug-based aids in psychological treatments. There will be risks, and difficult legal and ethical issues that will need to be addressed.

A topic that will almost certainly prove controversial in the next 20 years is the use of vaccines to make drugs ineffective. Already, people coming to hospital having overdosed on cocaine are given antibodies that mop up the drug in the blood. This is a short-term treatment, lasting a few hours, but in theory it should be possible to vaccinate someone against a drug, so that when a person takes it the immune system is turned on, stopping the drug from getting to the brain.

Vaccines for nicotine and cocaine are currently under clinical development to help addicted users. If this works, could or should we vaccinate people to protect them from developing an addiction in the first place, just as we do today with vaccines for polio and whooping cough? Even more controversial is the question of whether vaccines should be administered to children to immunise them against drug and alcohol use. Is it violating somebody's human rights to take away their choice to experience pleasure from a drug at some point in the future?

The therapeutic properties of psychedelics have hardly been studied over the last 40 years because of their legal status, but this kind of research is becoming more acceptable and will yield very interesting results. Drugs like psilocybin and ibogaine, psychoactive substances found in plants, are non-addictive themselves, and seem to be effective at helping people overcome addictions to other drugs such as opiates, alcohol and nicotine. Synthetics may be developed that have more predictable and less harmful effects.

We may be able to make better recreational drugs too. I have carried out research on replacing ethanol in "alcoholic" drinks with a safer alternative, such as a benzodiazepine; ideally these drinks would be impossible to get drunk on, producing a moderate buzz with no increase in effects at higher doses, and could be switched off at the end of the night with a "sober pill". It may be that by 2030 that's what we'll all be drinking in the pub. Or alcohol itself could be modified to make it safer and more pleasant. Alcohol works on a set of receptors with different functions: Alpha-1 receptors seem to control the sedative effect of alcohol, making you unsteady; Alpha-5 receptors make you lose your memory; and we think Alpha-2 or Alpha-3 receptors make you feel relaxed and happy. We might be able to make alcohol safer by combining it with chemicals that stop it affecting certain receptors. Ideally, we would develop an alcohol that targets just Alpha-2 or 3, giving us the sensation of relaxation and enjoyment without the negative effects.

By 2030, it's likely that every British child will have their DNA sequenced at birth, perhaps with the data stored on a microchip under their skin. It could help avoid many of the thousands of deaths a year that occur when people have allergic reactions to medication they are given in hospital, but could also help identify the possibility of drug dependency. We know a little about how genetic variations make people more vulnerable to the negative consequences of some drugs: a particular form of the serotonin transporter makes ecstasy users more likely to suffer depression; and variants on other genes can make you more likely to become dependent on alcohol, opiates or nicotine. Our present knowledge is only the tip of the iceberg, partly because full genetic sequencing is currently so rare.

There could be enormous benefits if millions of people share their genetic data and their experiences of illness, medication and drug taking on the internet. We'll be able to identify relationships between genes and drug effects, and inform people about their vulnerabilities in ways that will make both therapeutic and recreational drug taking much safer.

This is an edited extract from Drugs Without The Hot Air by David Nutt, published by UIT Cambridge at £12.99