Patient Experiences with Liquid Sildenafil Therapy

Homosildenafil and hydroxyhomosildenafil are analogues of sildenafil in which the N-methyl group on the piperazine ring has been replaced with an N-ethyl group or N-hydroxyethyl group, respectively. LC–MS has been used extensively in the analysis of synthetic PDE-5 inhibitors [3], [4], [5], [6], [7], [8], [9], [11], [12], [13], [14]. The fragmentation pathways of sildenafil were established by a comparison of the product ion spectra of sildenafil and eight sildenafil derivatives [15]. [10] detected homosildenafil in an herbal product and identified its structure through detailed nuclear magnetic resonance studies.

What special dietary instructions should I follow?

It is a thixotropic vehicle with a viscosity of approximately 1,000 cps at 25°C. Ora-Plus contains purified water, microcrystalline cellulose, sodium carboxymethyl cellulose, xanthan gum, carrageenan, sodium phosphate, and citric acid as buffering agents; simethicone as an antifoaming agent; and potassium sorbate and methylparaben as preservatives.8 Ora-Sweet syrup vehicle is a flavoring vehicle for oral extemporaneous preparations. It is flavored with a citrus-berry flavor blend and contains glycerin and sorbitol to prevent cap lock, a problem associated with many syrups. It is buffered to a pH of approximately 4.2 and it has an osmolality of about 3,240 mOsm/kg. Rockville, MD: U.S.

The effect of chronic ethanol ingestion on hepatic lipid peroxide, glutathione peroxidase and glutathione transferase in rat

Pharmacopeial Convention, Inc; January 2018.2. Extemporaneous sildenafil citrate oral suspensions for the treatment of pulmonary hypertension in children. Design and physicochemical stability studies of paediatric oral formulations of sildenafil. Extended stability of morphine and sildenafil for oral use in infants and young children. Allen LV Jr.

6.1 Clinical Trials Experience

Standard operating procedure for performing physical quality assessment of oral and topical liquids. Bethesda, MD: American Society of Health-System Pharmacists; 2016:1918-1932.7. To comment on this article, contact rdavidson@uspharmacist.com. Package insert / product label Generic name: sildenafil citrate Dosage form: powder, for oral suspension Drug classes: Agents for pulmonary hypertension, Impotence medications Adults Sildenafil is a phosphodiesterase-5 (PDE-5) inhibitor indicated for the treatment of pulmonary arterial hypertension (PAH) (World Health Organization [WHO] Group I) in adults to improve exercise ability and delay clinical worsening. Pediatric Patients (1 to 17 years old) Sildenafil for oral suspension is indicated in pediatric patients 1 to 17 years old for the treatment of pulmonary arterial hypertension (PAH) (WHO Group I) to improve exercise ability and, in pediatric patients too young to perform standard exercise testing, pulmonary hemodynamics thought to underlie improvements in exercise (1, 14) Adults: 20 mg orally three times a day. Homosildenafil was also detected in an herbal dietary supplement by Blok-Tip et al. [11], who found NMR data for the compound to be consistent with the data presented by Shin. In addition, the structures of two additional sildenafil analogues, hydroxyhomosildenafil and acetildenafil, were determined using LC–MS, direct infusion ESI–MSn, and nuclear magnetic resonance [11]. This paper reports on the detection and identification of a novel synthetic analogue of vardenafil found in an herbal dietary supplement. While the structure of the compound was tentatively established from the mass spectral fragmentation pattern, unequivocal proof of structure was shown by a comparison of its hydrolysis products to those of vardenafil.

Product	Dosage	Quantity + Bonus	Price
Viagra Generic	50mg	120 + 6 Pills	129.64€ 123.47€	Buy
Kamagra Oral Jelly	100mg	90 + 8 Sachets	303.56€ 289.10€	Buy
Viagra Generic	150mg	270 + 10 Pills	326.61€ 311.06€	Buy
Viagra Generic	100mg	60 + 4 Pills	96.36€ 91.77€	Buy
Kamagra	100mg	360 + 6 Pills	839.95€ 799.95€	Buy
Viagra Generic	200mg	60 + 4 Pills	125.19€ 119.23€	Buy
Viagra Generic	150mg	120 + 8 Pills	177.58€ 169.12€	Buy
Viagra Generic	100mg	360 + 10 Pills	330.21€ 314.49€	Buy
Kamagra Soft Tabs	100mg	84 + 4 Pills	233.05€ 221.95€	Buy
Kamagra	100mg	84 + 6 Pills	264.44€ 251.85€	Buy
Viagra Generic	200mg	270 + 10 Pills	379.76€ 361.68€	Buy

To our knowledge, this is the first report of a designer drug related to vardenafil. The data of a recent study have shown that SIL, acting via a nitric oxide (NO)-dependent mechanism, prevented indomethacin-induced gastropathy, possibly through a reduction of leukocyte adhesion and maintenance of gastric blood flow (Santos et al., 2005). (2009), SIL also attenuated airway inflammation and mucus production in the rat model, through the NO/cyclic guanosine 3′,5′-monophosphate pathway and significantly prevented renal damage by ameliorating oxidative and inflammatory injuries in diabetic rats. Inflammatory bowel diseases (IBD), namely ulcerative colitis and Crohn's disease, are two chronic idiopathic diseases characterized by prominent intestinal inflammation (Kirsner, 1995). The pathogenesis of IBD involves an interaction between genetic, immune and environmental factors. As a consequence, increased numbers of inflammatory cells are found in the intestine with chronic inflammation, resulting in an overproduction of proinflammatory mediators, such as cytokines, eicosanoids and reactive oxygen and nitrogen metabolites (Podolsky, 2000, Elson et al., 1995, Stober, 1988, Fiocchi, 1998, Katz et al., 1999). At present, medical treatment of IBD relays mainly on glucocorticoids, 5-aminosalycilic acid, and immunosuppressive agents, but the limitations in both efficacy and safety encountered continue to drive the search for better therapeutic options (Li et al., 2005). Given the importance of inflammatory cell activation involved in the development of IBD, there is a need for a treatment modality against IBD that can block the inflammatory processes, and advances in the understanding of the pathogenesis of IBD have created a trend of novel biological therapies that specifically inhibit the molecules involved in the inflammatory cascade (Nakamura et al., 1993). Sprague–Dawley rats of either sex (200–250 g; n = 8–12 per group) were kept in a room at a constant temperature 22 ± 1 °C with 12 h light/dark cycles and fed standard pellet chow and water ad libitum. The study was approved by Marmara University, School of Medicine, Animal Care and Use Committee. Sildenafil (Viagra; Pfizer, Ortakoy, Istanbul) tablets (50 mg) was obtained from commercially available sources and dissolved in tap water.

Side Effect	Frequency (%)	Severity	Onset Time	Reversibility	Recommendations
Headache	15-20	Mild	Within 1 hour	Reversible	Hydration, pain relievers
Flushing	10-15	Mild	Within 30 mins	Reversible	Reduce dose or skip dose
Nasal Congestion	8-12	Mild	30-60 mins	Reversible	Nasal sprays may help
Dyspepsia	5-10	Mild	1-2 hours	Reversible	Avoid spicy food, take after meals
Visual Disturbances	2-4	Mild	Variable	Usually reversible	Consult doctor if persistent

Drug solution was administered to the animals in a volume of 0.5 ml by The colonic wet weight of the colitis group (0.88 ± 0.12 g/100 g body weight) was significantly higher than that of the control group (0.33 ± 0.02 g/100 g body weight; p < 0.01). Treatment with SIL did not change the colonic weight of the colitis group (0.76 ± 0.12 g/100 g body weight) (Table 3). The macroscopic lesion score of the colitis group (5.60 ± 0.58) was reduced by SIL (2.58 ± 0.67) (p < 0.01). l-NAME treatment along with sildenafil citrate totally abolished the beneficial effect of SIL (5.56 ± 0.73) (p < The results of the present study demonstrate that daily SIL treatment of rats markedly improves TNBS-induced colonic lesions as confirmed by macroscopic examination and biochemical assays. Among several experimental models of IBD, administration of enema containing the Taken together, treatment with the specific PDE5 inhibitor sildenafil citrate is beneficial in TNBS-induced colitis in rats probably by NO-dependent and NO-independent mechanisms via the maintenance of oxidant-antioxidant status, prevention of apoptosis, superoxide production and cytokine release. The authors declare that there are no conflicts of interest.

Country	Approval Status	Regulatory Body	Allowed Dosages	Prescription Needed	Notes
USA	Approved	FDA	Up to 50 mg	Yes	Available under brand names and generics
European Union	Approved	EMA	20-50 mg	Yes	Sold by licensed pharmacies
Japan	Approved	PMDA	25-50 mg	Yes	Various formulations including liquids
Russia	Approved	RZN (Russian Federation)	20 mg	Yes	Licensing varies by manufacturer

The authors are grateful to Marmara University Scientific Research Project Commission for the financial support of this study (Project No: SAG-A-060510-0113).

Highlights of Prescribing Information

Pulverize the tablets, if used, to a fine powder. Add a small quantity of the Ora-Plus:Ora-Sweet mixture and mix to a smooth paste. Geometrically, add the remainder of the Ora-Plus:Ora-Sweet mixture to final volume and mix well. Use: Sildenafil citrate oral liquid has been used to treat pediatric pulmonary arterial hypertension in children in whom the risk-benefit profile of sildenafil is deemed acceptable. Packaging: Package in tight, light-resistant containers.1 Labeling: Keep out of reach of children.

Drug Interactions

Stability: A beyond-use date of up to 91 days may be used for this preparation.1-4 Quality Control: Quality-control assessment can include weight/volume, pH, specific gravity, active drug assay, color, rheologic properties/pourability, physical observation, and physical stability (discoloration, foreign materials, gas formation, mold growth).5 Discussion: A number of stability studies have been conducted on oral liquid formulations of sildenafil for pediatric use. From these, it appears that sildenafil is relatively stable in vehicles, with an acidic pH around 4 to 5. Sildenafil for oral suspension at 10 mg/mL (Revatio) is commercially available with a beyond-use date of 60 days after reconstitution. One study involved compounded sildenafil citrate in a citrate-buffered solution (0.1 M, pH 4) and either a syrup excipient (resulting in a suspension) or a sugar-free syrup excipient (resulting in a solution); both had pH values of approximately 4.2. Both the suspension and the solution were slightly pink and fruit-flavored.

Dig Dis Sci

The suspension demonstrated stability for 91 days at both 4°C and 25°C; however, the solution was stable only for 30 days, possibly related to a nonredispersible sediment at the bottom of the container.3 A study by Nahata and colleagues that involved sildenafil citrate tablets (Revatio 20 mg) with a mixture of 1:1 Ora-Sweet and Ora-Plus at 2.5 mg/mL and pH 4.5-4.7 demonstrated stability of 91 days at both 4°C and 25°C. Also studied was a mixture of 1:7 (1% methyl cellulose:simple syrup) at pH 5.1 to 4.9 that also demonstrated stability of 91 days at both 4°C and 25°C.4 Sildenafil citrate (C22H30N6O4S.C6H8O7, MW 666.70) occurs as a white to off-white, crystalline powder that is soluble 3.5 mg/mL in water. It is formulated as tablets equivalent to 25 mg, 50 mg, and 100 mg of sildenafil for oral administration. The tablets also contain microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hydroxypropyl methylcellulose, titanium dioxide, lactose, triacetin, and FD&C Blue #2 Aluminum Lake.6,7 Ora-Plus is an oral suspending vehicle that accepts dilution of up to 50% or more with water, flavoring agents, or syrups while still retaining its suspending properties. It has a pH of approximately 4.2 and an osmolality of about 230 mOsm/kg. Method of Preparation: sildenafil 200 mg Calculate the quantity of each ingredient for the amount to be prepared. Mix 50 mL of Ora-Plus with 50 mL of Ora-Sweet for use as the vehicle in this preparation.

Non-medical use

Homosildenafil and hydroxyhomosildenafil are analogues of sildenafil in which the N-methyl group on the piperazine ring has been replaced with an N-ethyl group or N-hydroxyethyl group, respectively. LC–MS has been used extensively in the analysis of synthetic PDE-5 inhibitors [3], [4], [5], [6], [7], [8], [9], [11], [12], [13], [14]. The fragmentation pathways of sildenafil were established by a comparison of the product ion spectra of sildenafil and eight sildenafil derivatives [15]. [10] detected homosildenafil in an herbal product and identified its structure through detailed nuclear magnetic resonance studies. Homosildenafil was also detected in an herbal dietary supplement by Blok-Tip et al.

Who should not take sildenafil?

[11], who found NMR data for the compound to be consistent with the data presented by Shin. In addition, the structures of two additional sildenafil analogues, hydroxyhomosildenafil and acetildenafil, were determined using LC–MS, direct infusion ESI–MSn, and nuclear magnetic resonance [11]. This paper reports on the detection and identification of a novel synthetic analogue of vardenafil found in an herbal dietary supplement. While the structure of the compound was tentatively established from the mass spectral fragmentation pattern, unequivocal proof of structure was shown by a comparison of its hydrolysis products to those of vardenafil. To our knowledge, this is the first report of a designer drug related to vardenafil.

CRediT authorship contribution statement

The data of a recent study have shown that SIL, acting via a nitric oxide (NO)-dependent mechanism, prevented indomethacin-induced gastropathy, possibly through a reduction of leukocyte adhesion and maintenance of gastric blood flow (Santos et al., 2005). (2009), SIL also attenuated airway inflammation and mucus production in the rat model, through the NO/cyclic guanosine 3′,5′-monophosphate pathway and significantly prevented renal damage by ameliorating oxidative and inflammatory injuries in diabetic rats. Inflammatory bowel diseases (IBD), namely ulcerative colitis and Crohn's disease, are two chronic idiopathic diseases characterized by prominent intestinal inflammation (Kirsner, 1995). The pathogenesis of IBD involves an interaction between genetic, immune and environmental factors. As a consequence, increased numbers of inflammatory cells are found in the intestine with chronic inflammation, resulting in an overproduction of proinflammatory mediators, such as cytokines, eicosanoids and reactive oxygen and nitrogen metabolites (Podolsky, 2000, Elson et al., 1995, Stober, 1988, Fiocchi, 1998, Katz et al., 1999). Obtain the required number of sildenafil citrate tablets or the required quantity of powder and place in a mortar. Pulverize the tablets, if used, to a fine powder. Add a small quantity of the Ora-Plus:Ora-Sweet mixture and mix to a smooth paste. Geometrically, add the remainder of the Ora-Plus:Ora-Sweet mixture to final volume and mix well. Use: Sildenafil citrate oral liquid has been used to treat pediatric pulmonary arterial hypertension in children in whom the risk-benefit profile of sildenafil is deemed acceptable. Packaging: Package in tight, light-resistant containers.1 Labeling: Keep out of reach of children. Stability: A beyond-use date of up to 91 days may be used for this preparation.1-4 Quality Control: Quality-control assessment can include weight/volume, pH, specific gravity, active drug assay, color, rheologic properties/pourability, physical observation, and physical stability (discoloration, foreign materials, gas formation, mold growth).5 Discussion: A number of stability studies have been conducted on oral liquid formulations of sildenafil for pediatric use. From these, it appears that sildenafil is relatively stable in vehicles, with an acidic pH around 4 to 5. Sildenafil for oral suspension at 10 mg/mL (Revatio) is commercially available with a beyond-use date of 60 days after reconstitution. One study involved compounded sildenafil citrate in a citrate-buffered solution (0.1 M, pH 4) and either a syrup excipient (resulting in a suspension) or a sugar-free syrup excipient (resulting in a solution); both had pH values of approximately 4.2.

• Liquid sildenafil citrate can be prepared by licensed compounding pharmacies.
• It is preferred by some for its rapid absorption and quick results.
• The liquid form eliminates issues with swallowing pills.
• Mixing with fruit juice or water can mask the bitter taste.
• Make sure the liquid is evenly mixed before each dose.
• Available in varying concentrations depending on medical needs.
• It’s essential to discuss health conditions with a doctor before use.
• Use caution if combining with nitrate medications, which can be dangerous.
• Some users find it more convenient for on-the-go use.
• Information on dosing should always come from a healthcare professional.
• Be aware of the potential for interactions with other drugs.

Both the suspension and the solution were slightly pink and fruit-flavored. The suspension demonstrated stability for 91 days at both 4°C and 25°C; however, the solution was stable only for 30 days, possibly related to a nonredispersible sediment at the bottom of the container.3 A study by Nahata and colleagues that involved sildenafil citrate tablets (Revatio 20 mg) with a mixture of 1:1 Ora-Sweet and Ora-Plus at 2.5 mg/mL and pH 4.5-4.7 demonstrated stability of 91 days at both 4°C and 25°C.

Before Using

Also studied was a mixture of 1:7 (1% methyl cellulose:simple syrup) at pH 5.1 to 4.9 that also demonstrated stability of 91 days at both 4°C and 25°C.4 Sildenafil citrate (C22H30N6O4S.C6H8O7, MW 666.70) occurs as a white to off-white, crystalline powder that is soluble 3.5 mg/mL in water. It is formulated as tablets equivalent to 25 mg, 50 mg, and 100 mg of sildenafil for oral administration. The tablets also contain microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hydroxypropyl methylcellulose, titanium dioxide, lactose, triacetin, and FD&C Blue #2 Aluminum Lake.6,7 Ora-Plus is an oral suspending vehicle that accepts dilution of up to 50% or more with water, flavoring agents, or syrups while still retaining its suspending properties. It has a pH of approximately 4.2 and an osmolality of about 230 mOsm/kg. It is a thixotropic vehicle with a viscosity of approximately 1,000 cps at 25°C. Ora-Plus contains purified water, microcrystalline cellulose, sodium carboxymethyl cellulose, xanthan gum, carrageenan, sodium phosphate, and citric acid as buffering agents; simethicone as an antifoaming agent; and potassium sorbate and methylparaben as preservatives.8 Ora-Sweet syrup vehicle is a flavoring vehicle for oral extemporaneous preparations.

Ingredient	Quantity per 30ml	Purity (%)	Source Organism	Additives	pH Level
Sildenafil Citrate	20 mg	99.9	Chemical Synthesis	Limonene, Glycerin	4.5
Glycerin	5 ml	—	Synthetic	Preservatives (None)
Deionized Water	24 ml	—	Purified Water	Buffering Agents
Flavoring Agents	0.5 ml	—	Plant Extracts	Artificial Flavors

It is flavored with a citrus-berry flavor blend and contains glycerin and sorbitol to prevent cap lock, a problem associated with many syrups. It is buffered to a pH of approximately 4.2 and it has an osmolality of about 3,240 mOsm/kg. Rockville, MD: U.S. Pharmacopeial Convention, Inc; January 2018.2.

• During use, note the onset time and duration of the liquid sildenafil's effect.
• Use with caution if you have heart, kidney, or liver issues.
• Always inform your healthcare provider of other ongoing treatments.
• Potential side effects can include nasal congestion or stomach upset.
• Avoid driving or operating machinery until you know how sildenafil affects you.
• Use only as directed; misuse can cause serious health issues.
• Liquid sildenafil citrate is sometimes compounded into topical gels.
• It’s crucial to maintain a record of dose and timing.
• Be aware that alcohol can impair the effectiveness of sildenafil.
• The medication does not protect against sexually transmitted infections.
• Seek emergency medical help if you experience symptoms like chest pain.

Extemporaneous sildenafil citrate oral suspensions for the treatment of pulmonary hypertension in children. Design and physicochemical stability studies of paediatric oral formulations of sildenafil. Extended stability of morphine and sildenafil for oral use in infants and young children. Allen LV Jr. Standard operating procedure for performing physical quality assessment of oral and topical liquids. Bethesda, MD: American Society of Health-System Pharmacists; 2016:1918-1932.7. To comment on this article, contact rdavidson@uspharmacist.com. Package insert / product label Generic name: sildenafil citrate Dosage form: powder, for oral suspension Drug classes: Agents for pulmonary hypertension, Impotence medications Adults Sildenafil is a phosphodiesterase-5 (PDE-5) inhibitor indicated for the treatment of pulmonary arterial hypertension (PAH) (World Health Organization [WHO] Group I) in adults to improve exercise ability and delay clinical worsening.

Why is this medication prescribed?

At present, medical treatment of IBD relays mainly on glucocorticoids, 5-aminosalycilic acid, and immunosuppressive agents, but the limitations in both efficacy and safety encountered continue to drive the search for better therapeutic options (Li et al., 2005). Given the importance of inflammatory cell activation involved in the development of IBD, there is a need for a treatment modality against IBD that can block the inflammatory processes, and advances in the understanding of the pathogenesis of IBD have created a trend of novel biological therapies that specifically inhibit the molecules involved in the inflammatory cascade (Nakamura et al., 1993). Sprague–Dawley rats of either sex (200–250 g; n = 8–12 per group) were kept in a room at a constant temperature 22 ± 1 °C with 12 h light/dark cycles and fed standard pellet chow and water ad libitum. The study was approved by Marmara University, School of Medicine, Animal Care and Use Committee. Sildenafil (Viagra; Pfizer, Ortakoy, Istanbul) tablets (50 mg) was obtained from commercially available sources and dissolved in tap water.

Simultaneous assay of sildenafil and desmethylsildenafil in human plasma using liquid chromatography-tandem mass spectrometry on silica column with aqueous-organic mobile phase

Drug solution was administered to the animals in a volume of 0.5 ml by The colonic wet weight of the colitis group (0.88 ± 0.12 g/100 g body weight) was significantly higher than that of the control group (0.33 ± 0.02 g/100 g body weight; p < 0.01). Treatment with SIL did not change the colonic weight of the colitis group (0.76 ± 0.12 g/100 g body weight) (Table 3). The macroscopic lesion score of the colitis group (5.60 ± 0.58) was reduced by SIL (2.58 ± 0.67) (p < 0.01). l-NAME treatment along with sildenafil citrate totally abolished the beneficial effect of SIL (5.56 ± 0.73) (p < The results of the present study demonstrate that daily SIL treatment of rats markedly improves TNBS-induced colonic lesions as confirmed by macroscopic examination and biochemical assays. Among several experimental models of IBD, administration of enema containing the Taken together, treatment with the specific PDE5 inhibitor sildenafil citrate is beneficial in TNBS-induced colitis in rats probably by NO-dependent and NO-independent mechanisms via the maintenance of oxidant-antioxidant status, prevention of apoptosis, superoxide production and cytokine release.

Alcohol interaction warning

The authors declare that there are no conflicts of interest. The authors are grateful to Marmara University Scientific Research Project Commission for the financial support of this study (Project No: SAG-A-060510-0113). Method of Preparation: sildenafil 200 mg Calculate the quantity of each ingredient for the amount to be prepared. Mix 50 mL of Ora-Plus with 50 mL of Ora-Sweet for use as the vehicle in this preparation. Obtain the required number of sildenafil citrate tablets or the required quantity of powder and place in a mortar. Pediatric Patients (1 to 17 years old) Sildenafil for oral suspension is indicated in pediatric patients 1 to 17 years old for the treatment of pulmonary arterial hypertension (PAH) (WHO Group I) to improve exercise ability and, in pediatric patients too young to perform standard exercise testing, pulmonary hemodynamics thought to underlie improvements in exercise (1, 14) Adults: 20 mg orally three times a day.

• The liquid form of sildenafil citrate is often prescribed for patients with swallowing difficulties.
• It provides quicker onset of action compared to traditional tablets.
• Some formulations are designed for sublingual or buccal absorption.
• This form allows for flexible dosing, especially in clinical settings.
• It should be kept out of reach of children and pets.
• Do not mix liquid sildenafil with other medications unless advised.
• Usage instructions often recommend shaking the bottle before use.
• This medication works by relaxing blood vessels in the penis.
• It should only be used under medical supervision to avoid interactions.
• Overdose can lead to severe side effects like vision changes.
• Consult a doctor for proper dosage and whether this form is suitable.