More money is to be invested in the treatment of drug misusers in England, the government has announced.
Health Secretary John Reid pledged £219m for drug treatment services by 2008. He said drug action teams' budgets would increase by 55% .
Mr Reid added that the funding would mean more specialist drugs workers and more in-patient treatment centres.
The National Treatment Agency said the extra funding would enable local services to be improved.
The Department of Health said £179m of the extra money would go directly to Drug Action Teams for the treatment of the 50,000 most seriously affected drug users.
This would include persistent offenders and drug misusers who also have alcohol and mental health problems, who often fail to complete treatment courses.
In addition to more specialist workers and in-patient detox treatment, the extra funding will help treat an extra 40,000 people and expand treatment for under 18s.
Scientific tests on a range of traditional remedies have shown they have "real benefits", researchers say.
Experts from King's College London said the treatments from around the world had properties which may help treat conditions such as diabetes and cancer.
The remedies included India's curry leaf tree, reputed to treat diabetes.
However complementary medicine experts said full clinical trials would have to be carried out to confirm the treatments' benefits.
The researchers examined Indian diabetes treatments, Ghanaian wound healing agents and cancer treatments used in China and Thailand.
They suggest their findings will help local people identify which plants to recommend and could lead to potential new compounds pharmacists to study.
Dr Nic Wilson from the University of London tested Internet-sold samples using a new technique that accurately spots the ingredients of tablets.
She told the British Pharmaceutical Conference in Manchester how many authentic-looking tablets were fakes.
Drug giant Pfizer, which manufactures Viagra, is conducting its own investigations into the fake copies.
Dr Wilson used a technique called near infrared (NIR) microscopy which provided a detailed picture of what was in each tablet.
This technology is similar to the older method called NIR spectroscopy but gives much more information.
Dr Wilson explained: "A counterfeit tablet may contain lactose as an ingredient in the bulk tablet, whereas the authentic tablet does not.
NIR spectroscopy could only show that the tablet is different, while NIR microscopy could actually identify the likely presence of lactose."
Many of the samples tested contained less of the active ingredient sildenafil than authentic Viagra.
They also contained different components from the bona fide Viagra.
Dr Wilson said: "We don't know that 'wrong' components will be harmful, but the user runs the risk of poor quality and possible toxicity, not to mention the fact that there is a high probability that the tablets have no clinical effect."
She said NIR microscopy should help regulatory authorities monitor the movement of counterfeit tablets.
It is the job of the Medicines Healthcare products Regulatory Authority to investigate any reports it receives of websites under its jurisdiction which appear to be in breach of regulations regarding advertising, or sale and supply of medicines.
In 2003, counterfeit Viagra with an estimated value in excess of £2.35m was seized.
Pfizer said it welcomed the research and was also analysing the samples.
A spokesman said: "We do not recommend that anyone obtains any prescription-only medicine online without seeing a doctor.
"Without knowing what ingredient is in a counterfeit medicine a patient could be putting their health at risk.
"It is important for men to see their doctor if they have erectile dysfunction as it may be an indicator of a more serious condition.
"Viagra may not be suitable for all men and there are also some men for whom sexual activity is not considered safe or for whom an oral treatment may not be appropriate."