Can Tadalafil (Cialis) increase blood flow to the lower extremities?

From the Guidelines

Tadalafil (Cialis) is not recommended as a first-line treatment to increase blood flow to the lower extremities, as the current evidence supports the use of cilostazol for this purpose. The medication works by inhibiting phosphodiesterase type 5 (PDE5), which causes blood vessel dilation throughout the body, not just in the genital area. This vasodilation effect can improve circulation to the extremities, including the legs. However, the most recent and highest quality studies, such as 1 and 1, recommend cilostazol as an effective therapy to improve symptoms and increase walking distance in patients with lower extremity peripheral artery disease (PAD) and intermittent claudication.

Key Points to Consider

• Cilostazol is indicated as a Class I treatment for patients with lower extremity PAD and intermittent claudication, with a recommended dose of 100 mg orally 2 times per day 1.
• The use of tadalafil for circulation issues is investigational and not FDA-approved for this purpose.
• Patients with circulation problems should consult their doctor rather than self-medicating, as leg blood flow issues could indicate serious underlying conditions requiring comprehensive treatment approaches beyond just medication.

Important Considerations

• The ability of tadalafil to relax smooth muscle in blood vessels explains its potential benefit for leg circulation, but this is not a recommended use according to current guidelines.
• Cilostazol has been shown to improve maximal walking distance by 40% to 60% after 12 to 24 weeks of therapy, and also improves walking ability and health-related quality of life 1.

From the Research

Tadalafil and Blood Flow to Lower Extremities

• The effect of Tadalafil on blood flow to the lower extremities is not directly addressed in all studies, but some provide relevant information 2, 3, 4.
• A study from 2023 found that daily low-dose Tadalafil (5 mg) increased capillary blood circulation in patients with type 2 diabetes and erectile dysfunction, as measured by nail fold capillaroscopy 2.
• Another study from 2008 discovered that Tadalafil treatment increased the number of functional circulating angiogenic cells, which contribute to vascular repair and may improve blood flow 3.
• However, a 2007 study on patients with Raynaud's phenomenon found that a single dose of Tadalafil (10 mg) did not increase digital blood flow at baseline or in response to heating, nor did it attenuate cold-induced vasoconstriction 4.
• It is essential to note that the studies have different focuses and patient populations, which may affect the generalizability of the results to the specific question of Tadalafil's effect on blood flow to the lower extremities 5, 6.

Mechanisms and Effects

• Tadalafil, as a phosphodiesterase type 5 inhibitor, has vasodilatory effects, which could potentially improve blood flow to various areas of the body, including the lower extremities 2, 3.
• The improvement in capillary blood circulation and the increase in functional circulating angiogenic cells suggest that Tadalafil may have beneficial effects on vascular health, potentially leading to improved blood flow 2, 3.
• However, the study on Raynaud's phenomenon and another on cerebral blood flow after stroke suggest that Tadalafil's effects on blood flow may be more complex and dependent on the specific condition and context 4, 6.

Patient Populations and Conditions

• The studies involved patients with various conditions, including erectile dysfunction, type 2 diabetes, Raynaud's phenomenon, and a history of stroke 2, 3, 4, 6.
• The effects of Tadalafil on blood flow to the lower extremities may vary depending on the underlying condition and individual patient characteristics 5, 2, 3, 4, 6.