The drug was subjected to stress conditions of hydrolysis, oxidation, photolysis, and thermal degradation. Considerable degradation was found to occur in peroxide hydrolysis. The stress samples were assayed against a qualified reference standard and the mass balance was found close to 99.9%.

Liquid Levitra offers an alternative to pills for convenience.
It is primarily used to treat erectile dysfunction.
Suitable for those with difficulty swallowing tablets.

The developed RP-LC method was validated with respect to linearity, accuracy, precision and robustness.

What should I do in case of OVERDOSE?

Phenylalanine is found in vardenafil oral tablets and vardenafil orally disintegrating tablets. This substance can be harmful to people with PKU. Tell your healthcare provider if you have PKU. They can suggest a different treatment option for you. Tell your healthcare provider if you have any of the following.

Cancer treatments

Heart problems, such as heart rhythm problems, chest pain, or heart failure Heart attack, stroke, or heart surgery within the past six months High blood pressure that is still too high despite taking medicines for it Peyronie's disease, or a penis with an abnormal curve or shape An erection lasting longer than four hours A blood disorder, such as sickle cell anemia An inherited eye disease called retinitis pigmentosa Vision loss, or a problem with the nerve between your eyes and brain (optic nerve) Health conditions or factors that raise the risk of optic nerve problems, such as diabetes, high cholesterol, smoking, being older than 50, or having a “crowded disc,” which is something an eye doctor may see during an eye exam Pulmonary veno-occlusive disease, a condition where blood vessels in the lungs are blocked People who can become pregnant are not usually prescribed vardenafil. It is not known if or how vardenafil could affect pregnancy or harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. People who can breastfeed are not usually prescribed vardenafil. It is not known if vardenafil passes into breast milk. American Journal of Analytical Chemistry, 3, 59-66. doi: 10.4236/ajac.2012.31009. Vardenafil and other ED drugs inhibit phosphodiesterase type 5 (PDE-5) enzyme, which in turn maintains higher levels of cyclic guanosine monophosphate, which relaxes smooth muscles, promotes penile blood flow, and enhances erectile function [1,2]. Pharmalogical studies indicate that interaction between PDE-5 inhibitors and certain drugs containing nitrates may drastically lower blood pressure [4].

Product	Dosage	Quantity + Bonus	Price
Levitra Soft Tabs	20mg	180 + 10 Pills	398.14€ 379.18€
Levitra Generic	20mg	180 + 10 Pills	293.10€ 279.14€
Levitra Generic	10mg	90 + 8 Pills	150.58€ 143.41€
Levitra Generic	40mg	20 Pills	67.56€ 64.34€
Levitra Original	20mg	8 Pills	65.05€ 61.95€
Levitra Generic	20mg	20 Pills	52.63€ 50.12€
Levitra Original	20mg	92 + 4 Pills	406.22€ 386.88€
Levitra Generic	40mg	120 + 8 Pills	302.37€ 287.97€
Levitra Soft Tabs	20mg	60 + 4 Pills	178.40€ 169.90€
Levitra Generic	10mg	360 + 10 Pills	407.94€ 388.51€
Levitra Original	20mg	14 + 2 Pills	102.27€ 97.40€
Levitra Generic	10mg	10 Pills	28.93€ 27.55€
Levitra Generic	40mg	10 Pills	41.37€ 39.40€
Levitra Generic	20mg	270 + 10 Pills	376.33€ 358.41€
Levitra Generic	60mg	120 + 8 Pills	372.33€ 354.60€
Levitra Generic	10mg	30 + 4 Pills	62.39€ 59.42€
Levitra Generic	20mg	90 + 8 Pills	180.78€ 172.17€

Despite the efficacy of PDE-5 inhibitors as a treatment for ED, their draw backs are also notable. Adverse effects such as head ache, facial flushing, dyspepsia, visual disturbances and muscle aches have been reported [3]. Recently, reports of blind ness have implicated Viagra [5].

5.3 Risk of Priapism

Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Grapefruit or grapefruit juice can raise vardenafil levels in your body, which can increase the risk of side effects. Vardenafil orally disintegrating tablets should not be taken with water or liquids. Let it dissolve on your tongue without crushing it. There are no known interactions between vardenafil and alcohol.

What should I tell my healthcare provider before taking vardenafil?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. In particular, make sure that you discuss if you are using any of the following before taking vardenafil. Tell your healthcare provider about all medicines that you take or have recently taken. This may not be a complete list of medicines that can interact with vardenafil. If you or someone else has taken too much vardenafil, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222. A few HPLC methods determination of vardenafil in bulk drug and biological samples were reported in the literature [6- 10]. All the above methods developed (references [6-10]) for the quantification of vardenafil and other PDE-5 inhibitors employed complex analytical instruments such as mass spectrophotometer for their estimation mainly in dietary supplements and bulk drug powders.

Country or Region	Approval Status	Regulatory Body	Availability	Notes
United States	Approved by FDA	Food and Drug Administration	Prescription-only	Classified as prescription medication
European Union	Approved in several countries	EMA	Prescription-only	Must adhere to local regulations
Canada	Approved by Health Canada	Health Canada	Prescription-only	Controlled substance
Australia	Approved by TGA	Therapeutic Goods Administration	Prescription-only	Requires prescription

As far as we are aware there is stability indicating UPLC method for the determination of related substances and for quantitative estimation of vardenafil. Hence, an attempt has been made to develop an accurate, rapid, specific and reproducible method for determination of vardenafil and all four impurities in bulk drug samples and in pharmaceutical dosage forms along with method validation as per ICH norms [11-13]. The stability tests were also performed on both drug substances and drug products as per ICH norms [14-16].

Ingredient	Concentration	Purpose	Notes
Vardenafil Hydrochloride	20 mg/mL	Active component for erectile dysfunction relief	Prescribed dose varies
Glycerin	10%	Solvent and base	Enhances absorption
Purified Water	Q.S. to 100%	Diluent	Ensures stability
Flavoring Agents	-	Improves taste	Commonly mint or berry

Samples of vardenafil HCl and its related impurities were received from Chiral Solutions private Limited.

Brand names

Tell your healthcare provider right away if you have any of the following symptoms of low blood pressure. People who are allergic to any of the following should not take vardenafil. Any of the ingredients in the specific product dispensed Your pharmacist can tell you all of the ingredients in the specific vardenafil products they stock. Vardenafil should not be taken while you are using certain other medicines. Before taking vardenafil, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

Drawing up the medication from the vial

See the Interactions section for more details. Do not take vardenafil unless it has been prescribed to you by a healthcare provider. Do not share vardenafil with other people, even if they have the same condition as you. Keep vardenafil out of the reach of children. Do not chew, cut, or crush vardenafil orally disintegrating tablets. Hyderabad, India (Figure 1).Commercially available 20 mg vardenafil tablets (Levitra) were purchased. LC grade acetonitrile was purchased from Merck, Darmstadt, Germany.

5.8 Hepatic Impairment

Take it as your healthcare provider recommends, which is usually about one hour before planned sexual activity. Do not take double or buy levitra fast extra doses. This survey is being conducted by the WebMD marketing sciences department. A Validated Rapid Stability-Indicating Method for the Determination of Related Substances in Vardenafil Hydrochloride by Ultra-Performance Liquid Chromatography () Kishore Kumar Kakumani, Kameswara Rao Chimalakonda, Rama Koti Reddy Yarram, Mukkanti Khagga DOI: 10.4236/ajac.2012.31009 PDF HTML 6,702 Downloads 13,358 Views Citations DOI: 10.4236/ajac.2012.31009 PDF HTML 6,702 Downloads 13,358 Views Citations A novel, sensitive, stability indicating RP-LC method has been developed for the quantitative determination of Varde- nafil and its related impurities in both bulk drugs and Pharmaceutical dosage forms. Effective chromatographic separation was achieved on a C18 stationary phase with simple mobile phase combination delivered in a simple gradient pro- gramme and quantitation was by ultraviolet detection at 210 nm. Analytical reagent grade Ammonium Bi carbonate were also purchased from Merck. High purity water was prepared by using a Millipore Milli-Q plus water purification system.

The onset of action may vary between individuals.
Sexual stimulation is necessary for effectiveness.
Use on an empty stomach may result in quicker action.

All samples and impurities used in this study were greater than 99.5% purity analyse by UPLC.

Advantage	Explanation	Compared to Tablets
Quick Absorption	Liquid form is absorbed faster than tablets	Faster onset
Easier to Swallow	Suitable for individuals with swallowing difficulties	Better for some users
Dose Flexibility	Can be measured precisely	More adaptable dosing
Faster Effects	Effects seen sooner after intake	More immediate results

The UPLC system, used for method development, forced degradation studies and method validation was a Waters Accquity Quaternary pump plus auto sampler and a photodiode array detector (MA, USA).The out put signal was monitored and processed using Empower software on Pentium computer (Digital Equipment Co). Photo stability studies were carried out in a photo stability chamber (sanyo, Leicestershine, UK).Thermal stability studies were performed in a dry air oven (Merck Pharmatech, Hyderabad, India).

7.3 Effects of Vardenafil on Other Drugs

Sexual activity can put extra strain on your heart, which may be unsafe for people with certain health problems, such as a recent heart attack. Talk to your healthcare provider to see if your heart is strong enough for sex. If you feel chest pain, dizziness, or nausea during sex, stop and contact your healthcare provider right away. Vardenafil does not protect against sexually transmitted infections, including HIV. Vardenafil belongs to a group of medicines, known as phosphodiesterase-5 (PDE-5) inhibitors, which are used to treat erectile dysfunction or pulmonary arterial hypertension.

Chromatographic conditions

You should not take more than one PDE-5 inhibitor medicine. Medicines in this group include avanafil (Stendra), sildenafil (Viagra, Revatio, and others), tadalafil (Cialis and others), and vardenafil (Levitra, Staxyn). Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if vardenafil is right for you. In particular, make sure that you discuss any of the following. The chromatographic column used was a Zorbax Extended C18 (100 × 2.1) mm with 1.8 µm particles.

Future directions in treatment

The mobile phase consisted of a buffer and acetonitrile delivered at a flow rate 0.25 ml?min–1. Buffer consisted of 20 mM Ammonium bi carbonate, pH adjusted to 5.0 by using ortho Phosphoric acid. In the developed UPLC method the resolution (Rs) between vardenafil and its four potential impurities was found to be grater than 2.0.Regrreation analysis showed an r value (correlation coefficient) grater than 0.999 for vardenafil and its four impurities. The inter and intra day precision values for all four impurities and for vardenafil was found to be with in 2.0% RSD. The method showed good and consistent recoveries for vardenafil in bulk drugs (98.8% - 100.9%), pharmaceutical dosage forms (100.5% - 101.5%) and its all four impurities (99.8% - 102.5%).The test solutions was found to stable in acetonitrile for 48 h. The mobile phase consisted of a mixture of buffer, acetonitrile. Buffer consists of 20 mM Ammonium bi carbonate pH adjusted to 5.0 with Ortho Phosphoric acid. The column temperature was maintained at 25˚C and the detection was monitored at a wave length of 210 nm .The injection volume 2 µl. A stock solution of vardenafil (500 µg·ml–1) was prepared by dissolving an appropriate amount in acetonitrile.