Sildenafil

Oral tablet (20mg, 100mg)Available in all 50 states

Marketing purposes only. Actual medications, if prescribed, are dispensed by a licensed pharmacy.

sexual health

SildenafilSildenafil

The original PDE5 inhibitor with a 4 to 5 hour duration of action, providing on-demand erectile function support. Also FDA-approved for pulmonary arterial hypertension (Revatio).

Rapid onset (30 to 60 minutes)

Well-established efficacy and safety

Available in low-dose for PAH

Generic, cost-effective

No commitment · HSA/FSA eligibleNo commitment · HSA/FSA eligible

How it works

Mechanism of action

Selectively inhibits PDE5, enhancing NO-mediated cGMP signaling in penile and pulmonary vascular smooth muscle, causing vasodilation.

The baseline panel.

Every Marek client receives this baseline panel before a provider review. Your provider may add additional biomarkers based on your health history, symptoms, and goals, pulling from 1,000+ available markers. See more biomarkers →

Hormone Profile

12 markers

Sex hormones

Total TestosteroneLC/MS
Free TestosteroneEquilibrium Dialysis
Estradiol, Sensitive / UltrasensitiveLC/MS
Sex Hormone Binding Globulin (SHBG)
ProgesteroneLC/MSFemale panel
Prolactin
Luteinizing Hormone (LH)
Follicle-Stimulating Hormone (FSH)
hCG, Total, QuantitativeFemale panel, pre-menopause

Adrenals & neurosteroids

Cortisol
DHEA-S

Growth hormone / IGF-1

Insulin-Like Growth Factor I (IGF-1)

Thyroid Status

3 markers

Thyroid hormones

Thyroid Stimulating Hormone (TSH)
Free T4
Free T3

Heart Health

9 markers

Cardiovascular health

Total Cholesterol
HDL Cholesterol
LDL Cholesterol
LDL:HDL Ratio
VLDL Cholesterol
Triglycerides
Apolipoprotein-B (ApoB)
C-Reactive Protein, High Sensitivity (hsCRP)
Lipoprotein(a) (Lp(a))

Metabolism

3 markers

Insulin sensitivity

Blood Glucose
Fasting Insulin
HbA1c

Organ Function

26 markers

Liver & pancreas

AST
ALT
Bilirubin, Total
γ-Glutamyl Transferase (GGT)

Kidney function

BUN
Creatinine w/ eGFR

Comprehensive Metabolic Panel (CMP)

Glucose
Blood Urea Nitrogen (BUN)
Creatinine
eGFR
BUN/Creatinine Ratio
Sodium
Potassium
Chloride
Carbon Dioxide, Total
Calcium
Protein, Total
Albumin
Globulin, Total
Albumin/Globulin (A/G) Ratio
Alkaline Phosphatase (ALP)
AST
ALT

Prostate health

Prostate-Specific Antigen (PSA)Male panel
Free PSAMale panel
% Free PSAMale panel

Nutrient Status

31 markers

Vitamins & minerals

Vitamin D, 25-OHD (25-Hydroxy)
Magnesium, RBC

Iron status

Iron
Iron Saturation
TIBC
UIBC
Ferritin

Complete Blood Count (CBC)

White Blood Count (WBC)
Red Blood Count (RBC)
Hemoglobin (Hgb)
Hematocrit (HCT)
MCV
MCH
MCHC
Red Cell Distribution Width (RDW)
Platelets
Neutrophils
Neutrophils (Absolute)
Lymphocytes
Lymphocytes (Absolute)
Neutrophil/Lymphocyte Ratio
Monocytes
Monocytes (Absolute)
Eosinophils
Eosinophils (Absolute)
Basophils
Basophils (Absolute)
Immature Cells
Immature Granulocytes
Immature Granulocytes (Absolute)
NRBC, w/ Reflex for Immature Cells

Clinical evidence

The research behind Sildenafil.

Sildenafil for Erectile Dysfunction: Pivotal Study

New England Journal of Medicine (1998)

Goldstein et al. demonstrated sildenafil significantly improved erectile function across all severity levels vs placebo.

Safety profile

Monitoring & safety information.

Commonly reported side effects

Headache
Flushing
Dyspepsia
Visual disturbance (blue tinge)
Nasal congestion

Less common but serious risks

Hypotension with nitrates
Priapism (rare)
NAION (very rare)
Hearing loss (very rare)

Generally not appropriate for

Concurrent nitrates
Severe hepatic impairment
Recent stroke/MI

Typical monitoring

Blood pressure
Visual symptoms
Erectile function assessment

FAQ

Quick answers.

The original PDE5 inhibitor with a 4 to 5 hour duration of action, providing on-demand erectile function support. Also FDA-approved for pulmonary arterial hypertension (Revatio).

Rapid onset (30 to 60 minutes). Well-established efficacy and safety. Available in low-dose for PAH. Generic, cost-effective.

Common side effects include: headache, flushing, dyspepsia, visual disturbance (blue tinge), nasal congestion. Most side effects are dose-dependent and may resolve with continued use or dose adjustment.

View all FAQs

See all FAQs

The original PDE5 inhibitor with a 4 to 5 hour duration of action, providing on-demand erectile function support. Also FDA-approved for pulmonary arterial hypertension (Revatio).

Treatments are dependent on licensed clinical prescription. Client costs vary based on individual labs and panel in treatments and services.