The general recommended dose of tadalafil is 10mg, which can be adjusted to 5mg or increased to 20mg, depending on individual potency and tolerance, with less than 50mg generally used. Tadalafil is a selective inhibitor of cyclic guanosine monophosphate-specific phosphodiesterase 5 and has the pharmacologic effect of promoting penile erection, subject to sexual stimulation. The dosage of tadalafil should be individualized, and the generally recommended dose is 10 mg, used up to once a day, taken at least 30 minutes before sexual activity. This can be increased to 20mg/dose or decreased to 5mg/dose depending on the potency and individual tolerance. Currently, the drug is used in less than 50mg, and the dose limit should be followed as directed, without increasing the dose or frequency of use. Tadalafil should not be used with nitrates and should be used with caution in people with underlying heart conditions, as sexual activity may pose a potential cardiac risk. Use may cause adverse reactions such as headache, back pain, myalgia, flushing, and indigestion. Tadalafil should be used in accordance with medical advice, do not adjust the dose and frequency of use arbitrarily, and seek medical attention if discomfort occurs during use.