Tadarise 40 mg (which contains tadalafil) should be avoided or used with caution in the following groups of patients:

Patients with Severe Heart Conditions: Those with severe cardiovascular problems, such as recent heart attack, stroke, or irregular heartbeats, should avoid Tadarise 40 mg because it may put additional strain on the heart.

Patients with Low Blood Pressure (Hypotension): Tadarise 40 mg can lower blood pressure further, so it should not be used by individuals with hypotension (low blood pressure).

Patients with Liver or Kidney Impairment: Those with significant liver or kidney issues may need adjusted doses or may be advised not to use this medication due to the risk of improper drug metabolism or excretion.

Patients with Retinitis Pigmentosa: Tadarise may worsen conditions like retinitis pigmentosa (a rare genetic eye disease), so it should be avoided in these patients.

Patients on Nitrates or Nitric Oxide Donors: The combination of Tadarise and nitrates (used for chest pain or heart conditions) can cause a dangerous drop in blood pressure, so this combination should be strictly avoided.

Patients with Allergy to Tadalafil: Individuals with a known allergy to tadalafil or any of the inactive ingredients in Tadarise should avoid it.

Patients with a History of Priapism: Priapism (prolonged and painful erections) is a rare but serious side effect. Those with a history of this condition should be cautious or avoid Tadarise 40 mg.

Patients with Severe Dehydration or Blood Cell Disorders: Those with conditions like sickle cell anemia or leukemia may have an increased risk of side effects, so they should consult their doctor before using Tadarise.

It's important to consult a healthcare professional to determine if Tadarise 40 mg is suitable for a particular patient, as individual health conditions and medications can influence its safety and effectiveness.