Combination of these three drugs namely Emtricitabine, Efavirenz and Tenofovir Disoproxil fumarate. It is used in the treatment of HIV or AIDS. It is either used itself or in combination with other antiretroviral medications. The combination of these three drugs reduces the single-dose pill burden and increases its effectiveness.
Efavirenz belongs to non-nucleoside reverse transcriptase inhibitors but emtricitabine and tenofovir belong to nucleoside analogues reverse transcriptase inhibitors. All these three drugs work by blocking the reverse transcription activity of viral genetic material.
The combination of these leaders was approved in the United state in 2006 and in the European Union in 2007. It is also marked on the WHO'S (World Health Organization's) list of essential and effective medicines.
Dosage Form:
The dosage form of these medications is available in a tablet. The tablet consists of 600mg of efavirenz, 200 mg of emtricitabine and 300 mg of tenofovir.
The doses of this medication depend upon age, body weight and stage of infection. The dosage and strength of this combination according to age and body weight are as follows:
- 12 years of age and weight of approx 40 kg or less: one tablet is taken empty stomach daily.
- 50 kg or more: additional 200mg per day of efavirenz is recommended along with the tablet.
Side Effects:
Some common side effects of this FDC combination Efavirenz Emtricitabine and Tenofovir are:
- Sleepiness
- Headache
- Trouble sleeping
- Unsteadiness
- Diarrhoea
- Nausea
- Dizziness
- Fatigue
- Depression
- Rash
Few severe adverse effects of this combination efavirenz emtricitabine tenofovir are:
- Serious psychiatric symptoms- several psychiatric disorders are seen and good Psychiatrist must be recommended.
- Nervous system symptoms (NSS) - disorder in the nervous system of the body.
- Worsening of renal impairment- sudden and Temporary loss of kidney function.
- Decreased in Bone mineral density - low bone mineral density may lead to osteoporosis
- Immune reconstitution syndrome- it is an inflammatory condition of AIDS in which the immune system tries to recover but last infections affect them
- Redistribution of body fat - fat disarrangement mainly occurred.
Drug Interactions:
The several drug interactions with these three combined drugs efavirenz emtricitabine tenofovir are as follows:
- Human immunodeficiency virus type 1 protease inhibitors: interaction of this combined drug with darunavir-ritonavir or lopinavir-ritonavir combination increases the concentration of tenofovir in the body. This combined drug is not administered with the atazanavir-ritonavir combination.
- Didanosine: tenofovir may increase the concentration of the didanosine which may lead to didanosine toxicity.
- Efavirenz: co-administration with efavirenz may cause either the change in concentration of other medications or change in concentration of efavirenz.
Contraindications:
In previous research, it was found that several patients suffer from hypersensitivity because of efavirenz.
Co-administration with voriconazole may decrease the concentration of voriconazole and increase the concentration of efavirenz.
