Sildenafil is a prescription medication for treating erectile dysfunction that belongs to a class of drugs called phosphodiesterase 5 (PDE5) inhibitors. These medications work by preventing an enzyme, phosphodiesterase type-5, from acting too quickly. This action increases blood flow to the penis following sexual stimulation, which helps to achieve and maintain an erection. The effectiveness of sildenafil is linked to the dosage, which is not a one-size-fits-all number. Determining the correct dosage is a medical decision made by a healthcare provider based on individual factors.
Available Sildenafil Dosages
Sildenafil for erectile dysfunction is available in three oral tablet strengths: 25 milligrams (mg), 50 mg, and 100 mg. Each dose is selected to balance effectiveness and tolerability. A healthcare professional’s goal is to find the lowest effective dose that produces the desired result while minimizing side effects.
The most common starting dose is 50 mg because it provides a good balance of efficacy and safety for most individuals. Many users find this dose sufficient to improve erections for sexual activity. This intermediate strength is an effective entry point for evaluating a patient’s response to the medication.
If the 50 mg dose is not effective enough, a doctor may prescribe the 100 mg tablet, which is the maximum recommended dose. This is reserved for when lower doses have failed to produce an adequate response. Conversely, the 25 mg dose is the lowest strength and is often recommended for men who experience side effects at higher doses or have certain health factors.
Factors That Influence Your Dose
Determining the right sildenafil dose is individualized, with providers evaluating several health factors. A patient’s age is a consideration, as men over 65 are often started on the lowest dose of 25 mg. This is because metabolic changes from aging can lead to higher exposure to the drug, increasing the potential for side effects.
Underlying health conditions also influence dosage. Severe liver or kidney disease can slow the body’s ability to process and eliminate sildenafil. This means the drug remains active for longer, so a lower starting dose of 25 mg is often necessary to prevent adverse effects.
A patient’s current medication list is another focus for safety. Nitrates, prescribed for chest pain, should not be used with sildenafil due to the risk of a dangerous drop in blood pressure. Alpha-blockers, used for high blood pressure or prostate issues, can also cause blood pressure to fall when taken with sildenafil, necessitating a lower starting dose of 25 mg. The severity of a patient’s erectile dysfunction may also guide the initial dosage.
How to Take Sildenafil for Best Results
For the best results, take sildenafil approximately 30 to 60 minutes before sexual activity. While it can begin working in as little as 30 minutes, its effects can last for up to four hours. The peak effect is usually within the first two hours.
Taking sildenafil with a high-fat meal can delay its absorption into the bloodstream. This delay means the onset of action will be slower and the medication may not be as effective. For the quickest results, it is best to take sildenafil on an empty stomach.
Sildenafil should not be taken more than once in a 24-hour period. Taking more than the recommended dose increases the risk of side effects without providing additional benefit. Remember that sildenafil does not automatically cause an erection; sexual stimulation is required for the medication to work.
Adjusting the Dose and Potential Side Effects
The initial sildenafil dose is not always the final one, as the dosage is often fine-tuned based on the patient’s response. If the initial dose is ineffective, a healthcare provider may increase it from 50 mg to 100 mg. This is only done if the patient has not experienced significant adverse reactions.
If a dose is effective but causes undesirable side effects, the doctor will likely decrease it. For example, a patient experiencing headaches or flushing on a 50 mg dose might be moved to the 25 mg dose. This lower dose may still be effective while reducing the side effects.
Common, dose-related side effects are often mild and temporary. These can include:
- Headaches
- Facial flushing
- Indigestion
- Nasal congestion
- Visual disturbances, like a blue tinge to vision
A rare but serious side effect is priapism, a painful erection that lasts for more than four hours. This condition requires immediate medical attention to prevent long-term damage.