Description
Kamagra Oral Jelly is sildenafil citrate in gel form, filled into single sachets instead of pressed into a tablet. The active substance is the same as in Sildenafil (Viagra): an inhibitor of phosphodiesterase type 5, the enzyme that breaks down cyclic guanosine monophosphate in erectile tissue. If cGMP persists, smooth muscle relaxes, arterial inflow rises and the expanding tissue restricts outflow by pressing on the veins.
The same caveat applies here as everywhere in this class: PDE5 inhibitors amplify an existing signalling chain, they do not start a new one. Without sexual stimulation no nitric oxide is released and no cGMP is produced. There is nothing to protect from breakdown.
The evidence for the active substance is overwhelming. Goldstein and colleagues showed clearly dose-dependent efficacy in the registration trial in the New England Journal of Medicine, Steers and colleagues supplied long-term data over 36 to 52 weeks from open-label extension studies. Galiè and colleagues studied the substance in a separate randomised trial in pulmonary arterial hypertension.
For the formulation itself the picture is different. That deserves saying plainly: there are no published pharmacokinetic comparisons of the gel against the tablet. The studies above were run on tablets. That the gel does not have to be swallowed and is easier to take is a handling matter, not a demonstrated claim about onset or bioavailability. Anyone claiming otherwise has no trial behind it. For the related vardenafil the difference between film-coated and orodispersible tablet is in fact documented explicitly. The two forms are documented as not interchangeable, which shows that different formulations of the same substance are not automatically equivalent.
The manufacturer is Ajanta Pharma, the originator of the Kamagra brand rather than a copy of it. One box contains seven 5g sachets in seven different flavours.
You can order Kamagra Oral Jelly as a box of seven sachets with 100mg sildenafil each.
This information is for research and educational purposes only. No medical advice.
Risks & Safety
The PDE5 class has one absolute contraindication that kills people every year because they do not know about it.
- Nitrates are an absolute contraindication: Nitroglycerin, isosorbide dinitrate, isosorbide mononitrate, amyl nitrite and the alkyl nitrites sold as poppers. Nitrates and PDE5 inhibitors act on the same signalling chain. Together, blood pressure can crash to life-threatening levels, even with hours between them.
- Alpha blockers: With tamsulosin, alfuzosin and similar agents the blood-pressure-lowering effects add up.
- Cardiovascular status: Sexual activity is physical exertion. With unstable angina, recent infarction or stroke, or severe heart failure, the question is not the drug but the exercise capacity.
- No data on the gel form: The efficacy and safety data come from tablets. There is no published pharmacokinetic work on the gel from which identical behaviour could be inferred.
- Dosing from a sachet: One sachet is a full 100mg unit. If you want less, you have to measure it out because a gel has no score line. That is less precise than splitting a tablet.
- Common adverse effects: Headache, flushing, dyspepsia, nasal congestion, visual disturbance with a blue tinge. Largely dose-dependent.
- Priapism: An erection lasting more than four hours is a urological emergency. Without treatment, permanent damage to erectile tissue is possible.
- Sudden loss of vision is grounds to stop and an emergency.
This classification does not replace medical advice. Risk and responsibility for any actual use lie entirely with the buyer.
Studies
- Oral Sildenafil in the Treatment of Erectile Dysfunction - New England Journal of Medicine 1998, Goldstein et al: registration trial on the dose-dependent efficacy of sildenafil.
- Assessment of the efficacy and safety of Viagra (sildenafil citrate) in men with erectile dysfunction during long-term treatment - International Journal of Impotence Research 2001, Steers et al: long-term data from open-label extension studies over 36 to 52 weeks.
- Sildenafil Citrate Therapy for Pulmonary Arterial Hypertension - New England Journal of Medicine 2005, Galiè et al: randomised trial on use in pulmonary arterial hypertension.
- Vardenafil orodispersible tablet - Drugs 2012, Sanford: cited as evidence that different formulations of the same PDE5 inhibitor are not automatically interchangeable. There, the orodispersible tablet consistently delivers greater systemic exposure than the film-coated one.
