From the outside, there is little that sets the three-bedroom house apart from its neighbours in this suburb of Stone Town. But inside, the building offers a rare lifeline to two dozen young men from across Zanzibar trying to kick their drug habits.
While reliable figures are hard to come by, specialists say there has been a significant increase in the use of hard drugs over the past few decades, and a corresponding increase in HIV prevalence among intravenous drug users (IDUs).
"When you stop using drugs you get so scared, you think you are going to die, but here you draw support from others. You ask why is the other person able to stop but not me?" Abdulrashid Salum, a recovering addict at the house, told IRIN.
The sober house provides classes on anger management, self esteem and drug relapse signs.
"We learn to accept that we are powerless against drugs, that we should avoid former leisure groups and the use of drugs such as alcohol to avoid sliding back into using drugs..." Salum added. "It is a dangerous thing to relapse; many end up in jail or dead. Relapse is a choice not bad luck."
The programmes are based on spiritual principles emphasizing abstinence and behaviour change, founder Suleiman Mauly said. "We have no counsellors, doctors or police here... it is based on people's free will to change," he said. The six-month programme costs about 100,000 Tanzanian shillings a month (US$74).
Meditation is a key component. "This helps recovering addicts to get rid of resentment. They identify situations which can cause them to relapse," said Mauly. Journal writing is encouraged and shared during peer sessions.
"It is from such sessions that we have learned the need to avoid engaging in promiscuous sexual relationships unlike in the past when this would happen when one was high," he added. Most affected are people aged 14-35, with marijuana and heroine most abused.
The sober houses are run by former addicts; rent is covered by the Detroit Recovery Project, while contributions from well-wishers meet other costs. Staff salaries are paid in kind too.
"We [former addicts] are experts to some extent, we know how it feels, the withdrawal effects, it helps make sense to the recovering addicts," Mauly said. "When you use drugs, you can influence others to use them, similarly when you are clean, you can influence them to recover."
Mauly, 29, who quit using heroin two years ago, recalled his experience: "I did not have any idea how powerful addiction was. I would try to limit my use to weekends but it did not work. I even tried substituting it with 'softer' drugs such as alcohol and marijuana, but failed.
"Addiction is a powerful disease, some of us were thieves and beggars; we have not come here from offices or mosques, so telling people to observe rules in the house after such a background is difficult."
The Zanzibar Association of Information Against Drug Abuse (ZAIADA) is among organizations linking affected youth to the sober houses through outreach workers and peer educators.
"When you ask them [the youth] why they use drugs, they say, because we are jobless," Mbarouk Said Ali, a programme officer with ZAIADA, told IRIN. Stone Town and the northern region, where most tourist resorts are located, are the most affected.
Easy access to drugs and the presence of many visitors to the island have fuelled drug availability, Mbarouk noted.
Long-term rehabilitation is, however, a problem. "We are seeking to build a skills training centre," he said. "For now, the most we can do is provide information and referrals for treatment."
With the community, ZAIADA is looking into supplying fresh syringes with a view to reducing HIV infection from syringe sharing by IDUs. "The community is okay with this as long as the reason is to prevent HIV," he said.
Zanzibar has a low HIV/AIDS prevalence in the general population at about 0.6 percent. However, HIV is more concentrated in high-risk groups such as drug users, men who have sex with men, and sex workers.
A 2006 government study found a link between substance abuse and HIV/AIDS. It showed that 30 percent of IDUs were HIV positive, compared with 12 percent of non-IDUs. Of the IDUs who shared needles, 28 percent were infected, against 5 percent who did not share needles.
Mohamed Dahoma, director of HIV/AIDS at the Ministry of Health and Social Welfare, told IRIN the number of drug abusers had been growing in Zanzibar. He said easier infiltration, as in most coastal areas, and a demand-driven supply were among the causes.
Surveys in 2005 and 2007 found a high correlation between drug use and high-risk behaviour, he said. "The surveys found that substance abusers were more likely to engage in flash-blood and needle sharing, low condom use and transactional sex," he said. Hepatitis B and C and HIV/AIDS were also documented.
The lack of trained personnel and insufficient funding are other challenges, Reychad Abdool, the regional HIV/AIDS adviser, Africa and Middle East, at the UN Office on Drugs and Crime (UNODC), told IRIN. UNODC is helping to build the capacity of government and civil society organizations to address drug abuse, including injecting drug use and related HIV prevention, and drug dependence treatment, Abdool added.
Meanwhile, the sober houses are helping to make a difference. "We are helping some drug users quit. We get a chance to save some lives," Mauly said. However, he added: "There are other issues such as the lack of jobs for former addicts. We do not want dry junkies [people who quit drugs but lack vision]."