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Jenagra
Last reviewed: 03.07.2025

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Jenagra is a selective cGMP PDE-5 inhibitor. The drug affects erectile function.
Indications Jenagry
It is used for therapy in the presence of problems with potency (to increase the ability to develop and maintain an erection during sexual intercourse).
Release form
The substance is released in tablets of 25, 50 or 100 mg. Inside the blister package there are 1 or 4 tablets. In the box - 1 package.
Pharmacodynamics
Sildenafil helps block the activity of the PDE-5 enzyme, which causes the accumulation of cGMP inside the cavernous bodies of the penis - thus, the drug has an indirect effect, without directly affecting the cavernous bodies. An increase in cGMP values causes active relaxation of the smooth muscle fibers inside the cavernous bodies, and in addition, increases the blood flow to the penis, which ensures a hard and stable erection during the entire sexual act.
The effectiveness of the drug directly depends on the desire and arousal of the man. During the process of arousal, nitric oxide is released, which is a participant in the activation of the enzyme guanylate cyclase. Due to this, accumulation and increase in cGMP values begins. The enzyme PDE-5 disrupts the activity of cGMP, but more active production of nitric oxide increases the severity of erection and its duration. Stronger accumulation of NO is noted under the influence of sildenafil.
If a man is not sexually aroused, the drug will not be able to provide the desired effect, because in such a situation there will be no initial trigger mechanism, which is associated with the secretion of the NO element. Jenagra affects the orgasm, slightly potentiating it, and in addition, it enhances the feeling of satisfaction from sex.
Pharmacokinetics
When taken orally on an empty stomach, the drug is rapidly absorbed. Bioavailability values are approximately 41%. Peak blood levels of sildenafil are detected after 0.5-2 hours. The primary effect is observed on average by the 60th minute. The rate of drug absorption decreases when combined with fatty foods. The degree of synthesis of the substance with albumin is 96%.
The substance is metabolized in the liver, via the P450 hemoprotein system, where it is transformed into the active breakdown product N-desmethyl sildenafil. The half-life is 4 hours.
Elimination in the form of metabolic products occurs mainly with feces, with another 13% excreted in urine.
In older people, blood levels of sildenafil are 40% higher.
In individuals with severe CRF, an 88% increase in Cmax is observed (due to a decrease in sildenafil clearance values due to the disease). In moderate or mild disease, such changes are not observed.
In people with liver failure, the clearance rate of sildenafil is also reduced, resulting in an increase in the Cmax level of the drug of up to 47%.
Jenagra does not have any negative impact on male fertility.
Dosing and administration
The drug should be taken orally, on an empty stomach (because in this case the development of the therapeutic effect occurs faster than when taking the drug with food). The drug is used 1 hour before sexual contact. To achieve the optimal effect of the drug, the man must be aroused.
The first single dose is 50 mg. If necessary (for example, if there is no effect), the dose can be increased to 0.1 g. The dose can also be reduced to 25 mg if the 50 mg dose has produced too strong an effect. Doses greater than 0.1 g are prohibited. There must be at least 24 hours between tablet administrations.
Men with moderate or mild CRF are prescribed the same dosages as healthy men. In severe cases of the disease or liver failure, it is recommended to initially take a dose equal to 25 mg.
If the patient is taking ritonavir, Jenagra should be taken at a dosage of 25 mg at intervals of 48 hours.
When combining sildenafil with itraconazole, ketoconazole, as well as saquinavir and erythromycin, it should be used in an initial dose of no more than 25 mg.
During therapy with drugs that block the activity of α-adrenergic receptors, the risk of orthostatic collapse must be taken into account, which is why treatment should be started with minimal doses of Jenagra.
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Contraindications
Among the contraindications:
- the patient has intolerance to sildenafil or other medicinal components;
- use in combination with nitrates, organic nitrites, and nitric oxide donors;
- use in individuals with concomitant cardiovascular disease in a severe form (for example, heart failure or unstable angina);
- the presence of an optic form of neuropathy, which is non-arterial in nature and develops in the anterior ischemic region (loss of vision is also observed against the background of the disease);
- liver failure of a severe nature;
- decreased blood pressure values;
- use in women and persons under 18 years of age.
Side effects Jenagry
Side effects often develop when using the drug in high doses. These signs are temporary and curable. In the case of taking Jenagra in therapeutic doses, it is tolerated without complications.
Sometimes there are moderate headaches, nasal congestion, facial hyperemia, changes in color perception and dyspeptic disorders. Occasionally, signs of priapism develop.
All the above-described manifestations are transient and do not require additional treatment procedures.
In case of individual intolerance, allergy symptoms may appear.
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Overdose
When doses of up to 0.8 g are administered, fairly strong side effects appear.
Symptomatic procedures are used to eliminate them. Since the drug is firmly synthesized with albumin, dialysis sessions will be ineffective.
Interactions with other drugs
Substances that inhibit the activity of hemoprotein P450 reduce the elimination of sildenafil, which increases the likelihood of negative symptoms.
Medicines that induce the activity of hemoprotein P450 prolong the half-life of the drug and also reduce the duration of its therapeutic effect.
Cimetidine, as well as drugs that inhibit the action of CYP 3A4, reduce the clearance rate of sildenafil, and also increase the risk of adverse effects.
Combining Jenagra with drugs that inhibit the activity of HIV proteases (such as ritonavir or saquinavir) increases the peak rate of absorption of the drug into the blood by 1000% and 140%, respectively.
A single use of antacids does not lead to changes in the pharmacokinetic properties of the drug.
Sildenafil increases the therapeutic properties of nitrates, which increases the risk of a significant decrease in blood pressure. For this reason, such drugs are prohibited from being combined.
Grapefruit juice affects the metabolic processes of the drug, resulting in an increase in its blood Cmax values.
Warfarin and tolbutamide do not interact with the drug.
Doxazosin in combination with the drug can lead to orthostatic collapse, but without loss of consciousness.
Jenagra does not have any negative interactions with antihypertensive drugs.
Sildenafil does not potentiate the effects of alcoholic beverages.
Storage conditions
Jenagra should be kept at temperatures not exceeding 25°C.
Shelf life
Jenagra can be used within 36 months from the date of release of the therapeutic drug.
Analogues
Analogues of the drug are Potenciale, Viagra, as well as Penimex and Vecta.
Attention!
To simplify the perception of information, this instruction for use of the drug "Jenagra" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.