A study of drug users around Dumfries found that most believed methadone had helped them reduce their habit.
Many users criticised a lack of privacy in pharmacies
But it also highlighted concern that the majority of people taking the heroin substitute were indulging in dangerous "topping up" on other drugs.
The peer research report was commissioned by the local drugs forum.
It found that while users in Nithsdale were generally happy with services they received they were often unaware of the programmes already on offer.
Nearly 80% of the people taking methadone who were interviewed said it had improved their drug problem.
However, 72% admitted taking other drugs while on the programme.
"Of those who were topping up 55% reported topping up with two or more drugs, commonly heroin and benzodiazepines," said the report.
"There is great cause for concern regarding those topping up while on methadone.
"They are at greater risk of overdose and some may be topping up with more than one drug.
"It has been highlighted that benzodiazepines are one of the main drugs found in drug deaths."
The report has recommended that people on the methadone programme be given more information about overdose risks.
The report sought the views of drug users on services in the area
The main areas where users wanted immediate help were housing problems, debt, boredom and advice on hepatitis and HIV.
In the longer term they expressed concern about their prospects of finding a job.
Another area of concern to drug users was the public manner in which they were treated.
"In both the methadone and needle exchange questionnaires, clients expressed their concern for the lack of privacy when attending the pharmacy," the report stated.
"In general clients reported the majority of staff from all services to be friendly and approachable.
"This is encouraging and commended, as staff attitude can make a difference to a client's self esteem."