Sildalis: two PDE5 inhibitors in one tablet

What makes this combination different

Most combination tablets pair two mechanisms — one for the erection, one for the timing. Sildalis pairs two drugs that do the same thing. Both sildenafil and tadalafil inhibit PDE5.

The reasoning is about kinetics rather than mechanism: sildenafil comes on faster, tadalafil lasts longer. In theory you get a quick start and a long window from one tablet.

The flip side, stated honestly

Because both act identically, the effects on blood pressure and on vessels elsewhere in the body add up. So does the side effect burden — headache, flushing and nasal congestion are reported more often with this combination than with either drug alone.

No regulator has licensed this pairing. That does not make it exotic, but it does mean there is no dossier of trial data behind the specific combination, only data on each component.

How the two parts work

Both block PDE5, the enzyme that ends an erection by clearing the messenger that keeps vessels in the erectile tissue relaxed. Blocked enzyme, sustained erection, provided arousal is present.

Sildenafil is largely gone within several hours. Tadalafil is still around the next day. That is the whole basis for putting them together.

Taking it

One tablet, roughly half an hour to an hour before sex, with water. Fatty food slows the sildenafil half; the tadalafil half is largely indifferent to it.

One tablet in twenty-four hours, and this is a case where that limit matters more than usual. Do not take any other PDE5 inhibitor alongside it or on the following day — tadalafil is still in your system.

Who should think twice

Anyone who has not used a PDE5 inhibitor before. Starting with a double-ingredient tablet means you learn nothing about how you tolerate either drug individually.

A single-ingredient tablet first is the more informative route. You can always move on.

Which effects turn up most often?

Headache, facial flushing, blocked nose, heartburn, muscle ache in the lower back, dizziness. The back ache comes from the tadalafil component and may arrive a day later.

Urgent attention: sudden vision loss, hearing loss on one side, chest pain during sex, or an erection that will not subside and becomes painful. The last one risks lasting tissue damage.

What must never be taken alongside

Nitrate medicines — nitroglycerin, isosorbide mononitrate, molsidomine — plus riociguat and poppers. The two act on the same mechanism, and the combined drop in blood pressure can be fatal rather than merely unpleasant.

This is not a precaution that scales with dose. It applies to the smallest tablet as much as the largest, and it has no safe interval.

What should it not be taken with?

Alpha blockers for prostate symptoms are a particular concern here because the blood pressure effect is already doubled. Ritonavir, ketoconazole, clarithromycin and erythromycin raise levels of both components.

Contraindications

Severe heart disease, recent heart attack or stroke, unstable angina, severe heart failure, uncontrolled blood pressure in either direction, severe liver or kidney impairment, inherited retinal disease.

With two active ingredients the margin for error is narrower. If you take anything daily, ask a pharmacist before the first tablet.

Buying it without prescription in the UK

You choose the strength and the pack size, add it to the basket and enter a UK delivery address. Nothing else is asked of you — no prescription to upload, no consultation, no call back.

Parcels go out in plain outer packaging with no product name and no logo, so nothing about the delivery suggests medication. How long it takes depends on where in the UK it is going and which shipping option you pick at checkout.

Prices are shown in pounds and follow pack size and strength. Larger packs come out lower per unit, and a generic sits below the branded equivalent while holding the same active ingredient. The scale is printed beside the quantity options.