Viagra Sildenafil interaction, detection and synthesis

There is no doubt that Viagra sildenafil is one of the most popular and effective discoveries of recent times. Though it has a good safety profile, you still need to exercise certain care while using this medication.

Also, if you are somebody who loves understanding the drug inside out, information about its detection in biological fluids and chemical synthesis will help you gain a better understanding of the drug.

Viagra Sildenafil – interactions

If you are taking treatment for HIV in the form of protease inhibitors, you need to be extra careful when you take this medication. This is because the protease inhibitors will acts as inhibitors of the process of metabolism of sildenafil. What this will result in is a multiplication of this drug’s plasma levels, which in turn will increase your chances of suffering from sildenafil side effects and also increase their severity.

If you are using protease inhibitors, you must limit your intake of Viagra sildenafil by not taking more than 25mg dosage every 2 days. Another interaction that you must be wary of, is the drug’s interaction with alpha blockers. If you use this drug with such a medication, there is a chance that you will experience a severe decrease in blood pressure. The only thing that you need to make sure of is that you need keep a gap of 4 hours between the intake of one drug and the next.

Detection of Viagra sildenafil

N-desmethylsildenafil is the main active metabolite of sildenafil. If you want to evaluate the pharmacokinetic status of those who are taking this medication for treatment of erectile dysfunction, you can quantify sildenafil and/or N-desmethylsildenafil in the whole blood, serum, or plasma of the patient.

Detection of sildenafil in biological fluids is essential if you want to check for potential poisoning or over dose in the case of forensic investigation.

Synthesis of Viagra sildenafil

The chemical synthesis of Viagra sildenafil is a 9 step process. The first step is methylation. The methylation of 3-propylpyrazole-5-carboxylic acid ethyl ester with hot dimethyl sulfate is the first step of the process. This is followed by hydrolysis using aqueous NaOH, where it’s converted to free acid. The third step is the process of nitration using fuming nitric or sulfuric acid. The next process is the formation of carboxamide using either NH4OH or refluxing thionyl chloride. The fifth step is the process of reduction of nitro into the amino group. Acylation with 2-ethoxybenzoyl chloride follows, which in turn is followed by cyclization. The last two stages of the synthesis are sulfonation to a derivative of chlorosulfonyl and condensation with 1-methylpiperazine.