Hello nholloway1013 Welcome to HCM First of all just to psycho-educate you I would like to tell you that there are endless harmful effects of Heroin Abuse. It is one of very dangerous substance which causes both psychological and physiological dependence. Apart from its effects it causes huge burden in terms of huge amount of money spend on getting heroin, individual may resort to crime to get money. It increases the chances of an individual to spend more time in rehabs. So please try to quit the habit and take help from good addiction medicine specialist. Its easy once you are motivated. Mode of use of this substance may be Snorting and it increases chance of respiratory infection, causes fibrosis in respiratory system, may lead to development of TB, depression of nasal bridge may occur. Injectable route is also very dangerous, it increases chances of spread of HIV, hepatitis B,C, and many other diseases. It causes fibrosis in blood vessels and some times gangrene to affected part also. Now coming to your query, dear friend, you are having inflammation at intravenous site, and it resulted in swelling, it is also called as Thrombophlebitis at injection site. It resulted in localized inflammation, collection of blood, severe soreness at injection site and may lead to development of fever also. what you can do is- - apply ice over affected part, which will decrease swelling and will help in clearing blood. - thrombophobe cream available at local chemist will fasten recovery and will decrease inflammation, pain. - for pain you can use any OTC medicine for pain. Hope I cleared your query. Thanks take care