Patient and Doctor Reviews of Sildenafil

Dr Nicholas Antonakopoulos

Medically reviewed by

Dr Nicholas Antonakopoulos

Last reviewed: 12 Mar 2019

What do people think of this medication?

A pack of Sildenafil reviewed by patients and doctors

Key takeaways

  • Patient reviews of Sildenafil are mostly very positive

  • Sildenafil is supported by doctors, the NHS, and the UK government

  • There are pros and cons to getting Sildenafil treatment

  • Trial and error is the best way to find out if Sildenafil is right for you

  • There are alternative treatments to compare Sildenafil to

What do reviews of Sildenafil show?

There are plenty of reviews of Sildenafil – Sildenafil (also sold under the brand name Viagra) is one of the most commonly used medicines for erectile dysfunction (ED). So, there are a lot of reviews from people who have used this medication before. A lot of patients and their partners found that trying Sildenafil has been a positive experience. In March 2019, Sildenafil held a patient satisfaction rating of 8.2/10 on

Below are some examples of patient and partner reviews of Sildenafil:

  • "I'm 58. I have had issues with my erection for about 5 years now and rarely have sex. Took 50mg Viagra. All I can say is FABULOUS! Took about an hour to kick in but then lovely firm erections for a number of hours. Managed a number of ejaculations which was another bonus. Side effects were dizzy spell, very mild headache."
  • "My husband is 16 years older than me and was diagnosed with diabetes and ED [erectile dysfunction]. Active 46 yr old at a healthy weight. 6' tall and about 180 lbs. He [used] to take OTC herbal supplements which worked with unreliable success but he finally talked to the dr and was given viagra samples. He takes 50 mg at a time. The viagra is much more reliable. He takes it right before foreplay and is rock hard right on cue 30 to 60 minutes later. Slight headaches sometimes but never enough to curb his appetite. Now his performance matches his desire and we both have multiple orgasms. It [definitely] works best on an empty stomach or low fat foods."

Statistics tell us that Sildenafil is:

  • Effective - it works in up to 87% of patients
  • Safe - there are side effects associated with taking Sildenafil such as dizziness and flushing, but this normally doesn’t stop people from using Sildenafil

Not all reviews are positive – there are reviews from people who have found using Sildenafil a less positive experience:

  • "Tried for 8 [months] after prostate surgery. Did not work. It gave me severe headaches the next day. Headaches decreased over 5 days. Headache medications gave no relief!"

What do doctor reviews of Sildenafil say?

Sildenafil is often first choice – In the UK, Sildenafil is usually the first medicine that is considered if a patient needs erectile dysfunction (ED) medication. Guidelines say that ED medicines (Sildenafil, Cialis, Levitra, and Spedra) are probably equally effective and medicines should be prescribed depending on what suits the patient’s lifestyle best. These considerations include:

  • Whether a patient is eligible for an NHS prescription for ED medicines. If not, Sildenafil is the cheapest option
  • Whether the patient would prefer to get medicines over the counter. Sildenafil is the active ingredient in Viagra Connect, which can be bought over the counter

Both the NHS and the Medicines and Healthcare products Regulatory Agency (MHRA) approve the use of Sildenafil for treating symptoms of ED.

ZAVA doctors are also supportive of the use of Sildenafil to treat ED: “Sildenafil is a safe and effective treatment for most men experiencing ED, providing all instructions are followed and the maximum daily dose is not exceeded,” says Dr Lisa Carter, one of our online doctor team.

There are drawbacks to using Sildenafil – some people might experience side effects such as dizziness, migraines, and visual disturbances. We also do not recommend using Sildenafil if you:

  • Have certain eye conditions: hereditary degenerative retinal disorders or a condition called NAION
  • Have recently had a stroke or heart attack
  • Are taking other medicines that can affect the heart

What are the pros and cons of Sildenafil?


  • People with erectile dysfunction (ED) are more able to get and keep an erection during sex
  • Better sexual performance can positively affect a person’s mental health and self esteem
  • Better sexual performance can also positively impact relationships
  • You can easily get an assessment for Sildenafil online
  • You only need to take Sildenafil when you need it (you don’t have to take it daily)


  • There is a risk of getting side effects from taking Sildenafil
  • Some people find that the medicine is too expensive for them
  • Some people have a condition or are taking medications which mean that they cannot use Sildenafil
  • Some people do not like taking medications
  • Sildenafil does not work as fast or as long as some other medications (Spedra and Cialis respectively)

How do different doses of Sildenafil compare?

Sildenafil is available in 25mg, 50mg, and 100mg doses – all of these doses are approved for use by doctors. The dose that we recommend you take is the lowest dose that your own body needs to get the desired effect. If you take a higher dose than what you need, you might not get a better effect but can be more at risk of side effects. The doses compare as follows:

  • 25mg – low dose, least likely to give side effects, least likely to work
  • 50mg – standard dose, has a medium chance of side effects and chance of working
  • 100mg – high dosage, most likely to work with highest chance of side effects

Picking the right dose – it is very difficult to predict which dose of Sildenafil your body needs to get an effect, so you may need to trial different doses to see the strength which works for you. Most people start on a 50mg dose. If this works for you, it might be worth considering trying the 25mg dose to see if you still get an effect with a lower risk of side effects. If this dose doesn’t work for you, you could try the 100mg to see whether you experience an effect. You should always talk to a doctor first before making any changes.

How to make a decision about getting Sildenafil?

Check you’re safe to take it – the first step to deciding whether Sildenafil is the right choice for you is to have a consultation with a doctor. In the consultation, the doctor may ask you questions to help determine the causes of your erectile dysfunction (ED) symptoms and whether Sildenafil is a suitable treatment option for you.

Trying it out is the best way – if you so decide to try Sildenafil:

  • Make sure that you try Sildenafil a few times as it may take time for your body to get used to the medicine. Some men find that they do not get an effect from Sildenafil straight away
  • Check for the common side effects – dizziness, visual changes, headaches, feeling sick (nausea). Weigh up if the side effects that you experience are worth the benefits of taking the medicine
  • Give the medicine the best chance of working by avoiding taking it with a big meal or drinking alcohol. Taking Sildenafil with a big meal might delay the absorption of the medicine into the system, whilst drinking alcohol produces the opposite effect to Sildenafil

Buy it in an erectile dysfunction trial pack – you may want to consider our trial pack of ED medicines to compare the effect of Sildenafil (in the form of Viagra) to the other ED medicines.

How does Sildenafil compare to other treatments?

It’s as effective as similar medication – Sildenafil and the other erectile dysfunction (ED) medications (Cialis, Levitra, and Spedra) are about as effective as each other. They all carry the same risk of side effects (such as dizziness, vision changes, and headaches) but often people decide that the benefits outweigh these risks.

Some medications are faster – Sildenafil usually takes between 30 to 60 minutes to work. While Viagra works in the same way, this is slower than some medicines such as Levitra and Spedra, which can work as soon as 15 to 30 minutes after you take it. Some people find that if they don’t want to plan sex far in advance then other ED medications such as Levitra or Spedra may suit them better.

Some medications last longer – Sildenafil works for up to 4 hours after you take the medicine, which is similar to Levitra and Spedra. Cialis works for much longer, with some men reporting that it works for up to 36 hours after they first take it. This means that Cialis is also an option if you do not want to plan sex far in advance.

There are no good herbal alternatives to Viagra – some people may look for herbal or natural alternatives to ED medicines. However, there is not as much research that has gone into seeing how well these work, or how safe they are as treatment options. So, we cannot guarantee for sure that these herbal medicines are effective and safe in the same way that we can say about the conventional ED medicines.

There are treatment options other than medication – people may consider using non-medicine treatment options such as psychosexual counselling in the case of performance anxiety. This can be effective if the cause of ED symptoms are psychological, and can of course be combined with Sildenafil and other medicines.

Medically reviewed by:
Dr Nicholas Antonakopoulos Accreditations: MBBS, BSc

Dr Nicholas Antonakopoulos graduated from the University of London in 2006. He did his postgraduate training in hospitals in the London area, and he trained for four years in Trauma and Orthopaedic Surgery before completing his training in General practice in 2015.

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Last reviewed: 12 Mar 2019

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