Provide your CV to agencies after they take the time to listen to your needs in person. Agency staff working in a ‘non commission’ based team will more readily share you and consider you for all jobs as they arise.
Be blunt with the agencies. Ask them which client companies they represent regularly. How many similar roles in your location have they had in the past 12 months? Do they submit CVs speculatively, if so take great care this could mean a valid detailed future representation from a preferred partner is ignored. Do they change your CV before submission, if so can you see it? How many people have they placed with your skills in the last 6 months and with whom and where?
Will they let you speak to people they have placed in the companies prior to interview? If they don’t provide you with information freely, consider going elsewhere - there are endless options.
Don’t let any agency require you to sign up 'selectivity' - it’s not a wise move. You will need to work with 3-4 agencies to gain access to all the major employers, as most employers only work with a few select agencies.
Register with on-line job sites, particularly Inpharm, Pharmiweb, Jobsite, Monster, Jobsearch, Emedcareers. You may get a better response if you apply for specific roles on these sites, rather than just loading your CV as it may be submitted without your consent to several places. Set yourself up for valid tailored bulletins on sites where you can.
Try to build a consistent working relationship with 1-2 agencies discussing all options you see so that you reduce the iteration in discussion and get priority attention and timely/accurate representation.