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.
Causes of low blood pressure: Heart disease. 1  Weakened heart muscle can cause the heart to fail and reduce the amount of blood it pumps. 2  One common cause of weakened heart muscle is the death of a large portion of the heart's muscle due to a single, large heart attack or repeated smaller heart attacks.he most common example of tachycardia causing low blood pressure is atrial fibrillation. Atrial fibrillation is a disorder of the heart characterized by rapid and irregular electrical discharges from the muscle of the heart causing the ventricles to contract irregularly and (usually) rapidly.