Clients affected by substance misuse may have difficulties prioritising their own healthcare and some will have difficulties adhering to some contraceptive methods and a LARC method is likely to be the most appropriate option.
For vulnerable clients, sharing information with relevant professionals, eg risk of pregnancy, cannot be emphasised strongly enough and this should be discussed with clients. They can be offered referral for preconception counselling and supported to involve their key worker/social worker in the event of a pregnancy.

Clients affected by drugs or alcohol who can consent to treatment, should be given the same care as any other client. Due to their sometimes fluctuating mental states it is especially important to ensure that, at the time of consent to treatment, they are fully aware of all the implications and that this is documented clearly. On rare occasions where a client appears to be incoherent, but has presented for advice, the case and management should be discussed with a senior colleague.

All patients should be offered regular sexual health testing ie HIV, syphilis, gonorrhoea and chlamydia. Some drug users may also require testing for hepatitis B & C and some may require vaccination for hepatitis B. There is currently an HIV outbreak amongst people who inject drugs (PWIDs) in Glasgow.

Different drugs may pose different risks for those requiring contraception.

1. Hepatitis C
   If a client is known to have hepatitis C, it is useful to know whether she has attended specialist services. She is likely to know if her disease is active or has resolved.
   Checking LFTs may guide your choice of contraception but should not delay it as the client may not return. For women on treatment for hepatitis C it is essential to ensure effective contraception as RIBAVIRIN is teratogenic. Effective contraception should be used while on Ribavirin and continued after completing the treatment for 4 months for females, 7 months for males.For hepatitis patients the use of Nexplanon, and IUS or IUD is recommended.
   Oestrogen-containing methods are UKMEC 3/4 (likely unacceptable health risks) for initiation and UKMEC 2 for continuation for women with active viral hepatitis. For women with stable disease and normal liver function these methods can be considered UKMEC 1.
   Progestogen-only methods are UKMEC 1 for women with active viral hepatitis.                         
2. Venothromboembolism
   Women who inject drugs are at risk of VTE as the drugs they inject are usually cut with various impurities which can cause vascular damage in addition to repeated trauma. Oestrogen containing contraceptives should be avoided if a woman has a history of VTE (UKMEC 4) or is an injecting drug user. All progestogen methods are UKMEC 2 and so can be used.                                                                                                                                              
3. Fatty Liver and Cirrhosis
   Fatty Liver is a reversible stage of alcoholic liver disease and resolves when alcohol intake decreases. Alcoholic hepatitis will occur (in 20-30%) if drinking continues to excess; about 10% of patients develop cirrhosis with continued drinking. For women who have mild cirrhosis without complication, all methods can be considered UKMEC 1.For women with severe decompensated cirrhosis, oestrogen methods should be avoided (UKMEC 4).Progestogen only methods can be considered after expert review (UKMEC 3). Copper IUD is UKMEC 1.

Scottish Drug Services Directory
http://www.scottishdrugservices.com/

FSRH. UK Medical eligibility criteria for contraceptive use. July 2016.
UKMEC (pagelizard.com)