Phosphodiesterase 5 inhibitors
What are phosphodiesterase 5 inhibitors?
Phosphodiesterase 5 (PDE 5) inhibitors are a type of targeted therapy used to treat people with pulmonary hypertension (PH). Targeted therapies slow the progression of PH and may even reverse some of the damage to the heart and lungs.
There are two types of PDE 5 inhibitor currently used to treat PH:
- sildenafil (Viagra or Revatio)
- tadalafil (Adcirca).
PDE 5 inhibitors are also used to treat erectile dysfunction. This is because the body has the same type of cells in the blood vesselsSomething that blood passes through, such as a vein or artery. of the lungs as the blood vessels of the penis. Viagra (sildenafil) has been used to treat erectile problems since 1998.
PDE 5 inhibitors are taken as tablets.
How do phosphodiesterase 5 inhibitors work?
PDE 5 inhibitors stop a particular enzymeA type of molecule in the body, which has a specific function. Some enzymes involved in controlling blood vessel constriction (such as PDE5) can be targeted by drugs used to treat PH. (phosphodiesterase type 5 [PDE5]), found in blood vessel walls, from working properly. PDE5 helps control blood flow to the pulmonary arteries.The blood vessel delivering blood to the lungs from the right side of the heart. By stopping PDE5 from working, PDE 5 inhibitors (ie sildenafil and tadalafil) cause the blood vessels to relax. This increases blood flow to the lungs and lowers blood pressure.
How do sildenafil and tadalafil work?
Risks associated with taking phosphodiesterase 5 inhibitors
Like all medicines, PDE 5 inhibitors are associated with some risks.
PDE 5 inhibitors are known to interact with certain types of medicine. Your PH specialist will discuss the types of drugs you should avoid if you are taking PDE 5 inhibitors.
Your PH team will discuss all the risks associated with taking PDE 5 inhibitors with you.
