Getting Context from Fragment extended Activity

I have an "app" that has a tab layout with three tabs: In the first i'm trying to retrieve some rows from a SQLite database and show them in a ListView. The class which handle the tabs layout is called PageFragment:

public class PageFragment extends Fragment {
public static final String ARG_PAGE = "ARG_PAGE";

private int mPage;
public MainActivity Main;

public static PageFragment newInstance(int page) {
    Bundle args = new Bundle();
    args.putInt(ARG_PAGE, page);
    PageFragment fragment = new PageFragment();
    fragment.setArguments(args);
    return fragment;
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mPage = getArguments().getInt(ARG_PAGE);
}

ListView ItemsLst;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view = null;
    switch(mPage)
    {
        case 1:
            view = inflater.inflate(R.layout.layout_schedule, container, false);

            DatabaseHandler db = new DatabaseHandler(getActivity().getApplicationContext());

            Medicine med = new Medicine("Cardioaspirina", "Pillola", 1, "2015-02-25", "12:00:00");

            db.AddMedicine(med);

            ScheduleList(view, db.GetAllMedicines());

            return view;
        case 2:
            view = inflater.inflate(R.layout.layout_settings, container, false);
            return view;
        case 3:
            view = inflater.inflate(R.layout.layout_info, container, false);
            return view;
    }
    return view;
}

public void ScheduleList(View v, List<Medicine> medicines) {
    ItemsLst = (ListView) v.findViewById(R.id.listview);
    ArrayAdapter<Medicine> adapter = new ArrayAdapter<Medicine>(getActivity(), android.R.layout.simple_list_item_1, medicines);
    ItemsLst.setAdapter(adapter);
}

}

As you can see, in the onCreateView() method i manage the tabs layout. To retrieve data from the database i created a class named DatabaseHandler which has methods like AddRecord, GetRecord, GetAllRecords, etc. The issue is that the DatabaseHandler constructor needs a Context variable and i tried to give it the context using:

DatabaseHandler db = new DatabaseHandler(getActivity().getApplicationContext());

I also tried to use only getActivity() but it throws me NullPointerException.

If useful, here is the DatabaseHandler constructor:

public DatabaseHandler(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

So anyone knows how to get the application context from the PageFragment class? Thank you in advance!