Fentanyl is available as a skin patch, lozenge, pills, shots, a film that dissolves in your mouth, nasal spray, or by IV (intravenous) . Use fentanyl exactly as prescribed by your doctor. This is very important so that you do not get too much of the drug.entanyl is available as a skin patch, lozenge, pills, shots, a film that dissolves in your mouth, nasal spray, or by IV (intravenous) . Use fentanyl exactly as prescribed by your doctor. This is very important so that you do not get too much of the drug.
Some medical conditions can cause low blood pressure. These include: 1  Pregnancy. 2  Because a woman's circulatory system expands rapidly during pregnancy, blood pressure is likely to drop. 3  This is normal, and blood pressure usually returns to your pre-pregnancy level after you've given birth.
Some experts define low blood pressure as readings lower than 90 mm Hg systolic or 60 mm Hg diastolic â you need to have only one number in the low range for your blood pressure to be considered lower than normal.