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Viagra

Last updated on 14/07/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Sildenafil

CHINESE NAME: 威而鋼、偉哥

DRUG CLASS: Antihypertensives, Vasodilators

SUB CLASS: Phosphodiesterase Inhibitors

USED FOR: Erectile dysfunction

AVAILABLE DOSAGE FORMS:
– 25 mg, 50 mg, 100 mg (tablets)
– 50 mg (orodispersible tablets)

What is Viagra?

Viagra is a brand of products used to treat erectile dysfunction (impotence) in men. It contains Sildenafil, which belongs to a class of medications called phosphodiesterase inhibitors. Viagra works by increasing blood flow to the penis during sexual stimulation, which can cause an erection.

How to use it?

Viagra can be taken by mouth, with or without food.

Erectile dysfunction
Adult
50 mg approximately 1 hour before sexual intercourse, may adjust depending on response. Maximum dosage is 100 mg daily.

What are the side effects of Viagra?

Common side effects of Viagra include anemia, anxiety, diarrhoea, dizziness, fluid retention, gastrointestinal discomfort, headache, insomnia and tremor.

Who should not take Viagra?

– People allergic to Viagra or any component of the formulation.
– Patients who are currently taking nitrates regularly or as emergency medication
– Patients who recently had myocardial infarction or stroke

Pharmacist Tips:

– This medication can make you dizzy. Avoid driving or operating machinery until you know how you respond to Viagra.
– Report to your doctor immediately if you experience sudden visual or hearing loss.
– Seek medical assistance in case of prolonged erection (over 4 hours).
– Do not confuse Revatio with Viagra, which also contains Sildenafil but indicated for pulmonary arterial hypertension.

Common dosing schedule:
Take Viagra approximately 1 hour before sexual intercourse, but not more than once per day.

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Viagra may interact with:
– Nitrates, e.g. Nitroglycerin, Nitric oxide, Isosorbide Mononitrate and Dinitrate
– Nicorandil

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Viagra in Hong Kong?

In Hong Kong, Viagra is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at https://www.drugoffice.gov.hk

Need more information?

For detailed information about the use of Viagra in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.