Guides

Tables and diagrams

We’ve collected key tables and diagrams in the guide here for ease of reference.

When not on treatment, your immune system works in overdrive

CD4 increases on ART

Chart showing how CD4 increases on ART

Drug levels with good adherence

Good drug levels

Drug doses are calculated so that average drug levels are high enough to be active against HIV for 24 hours a day. They are also low enough to minimise the risk of side effects.

A missed or late dose increases the risk of resistance

Missed dose = low drug levels

Missing or being late with a drug lets the drug levels fall to a level where resistance can develop. The more often you are late, the greater the chance of resistance.

The main types of hiv drugs

Abbreviation Full name(s)
NRTIs/NtRTIs (“nukes”) Nucleoside/tide reverse transcriptase inhibitors or nucleoside/tide analogues
NNRTIs (“non-nukes”) Non-nucleoside reverse transcriptase inhibitors
PIs Protease inhibitors
INIs (or INSTIs) Integrase (strand transfer) inhibitors
CCR5 inhibitors CCR5 inhibitors are a type of entry inhibitor
Fusion inhibitors Fusion inhibitors are a type of entry inhibitor

HIV lifecycle – how drugs work in different ways

If a CD4 cell is infected by HIV, this cell is used to produce hundreds of new copies of HIV. Different drugs block different parts of this HIV life cycle.

First combination meds

UK guidelines include starting treatment with two nukes plus a third component.

Table 2: Summary recommendations for choice of ART in the UK
PREFERRED ALTERNATIVE*
Two nukes tenofovir + emtricitabine (Truvada) abacavir + lamivudine (Kivexa) **
Plus a third component atazanavir – boosted PI or
darunavir – boosted  PI  or
dolutegravir – integrase inhibitor  or
elvitegravir – boosted integrase inhibitor or
raltegravir – integrase inhibitor  or
rilpivirine  – NNRTI *
efavirenz (NNRTI) ***

Adapted from BHIVA guidelines (June 2015, draft).

* Drugs that can only be used in some situations. Rilpivirine can only be used when viral load is less than 100,000 copies/mL. Abacavir can only be used if the HLA B-5701 test is negative.

** abacavir + lamivudine (Kivexa) can be used at any viral load when used with dolutegravir. Otherwise, Kivexa can only be used when viral load is less than 100,000 copies/mL

*** Although efavirenz is no longer a prefered drug, it might still be offered in some clinics.

Last updated: 1 October 2019.